1. Shaquille O'Neal

He's a platinum-record-making rapper (Shaq Diesel), a genie trapped in a magical boombox (Kazaam) and a sheriff and an honorary deputy U.S. Marshal in his free time. He's a business school graduate (University of Phoenix online, Class of 2005), a martial artist in an eponymous video game (Shaq Fu) and a freestyle rapper who burns bridges with former teammates. What else? He's a reality television star ("Shaq Vs."), a four-time NBA champion, and the most popular athlete on Twitter. He has approximately 15 nicknames (Wilt Chamberneezy is, arguably, the best) and quietly, anonymously, donates truckloads of money to philanthropic causes. When he's inducted into the Hall of Fame next decade, let's just hope his plaque has enough space for it all.

2. Charles Barkley

Admit it: If you lived in the state of Alabama, you'd think long and hard about voting for Barkley as your governor in 2014. Of course, there is a virtually endless list of reasons not to as well. Start with his actual political affiliation being ambiguous at best; over the past 15 years, he went from self-identifying as a Republican, to supporting Barack Obama, and then, most recently, to being an Independent. Then there's his DUI, in December of last year, wherein Barkley explained that he was rushing to pick up a female passenger for a sex act. (On second thought, that doesn't disqualify him from politics at all.) But he's also the most entertaining retired athlete on earth. And selfishly, you think, maybe that's reason enough.

3. Ron Artest

There is no match more perfect than Artest and Hollywood. The man has a record label (Tru Warier Records) and compulsively interacts with fans via three (count 'em, three) Twitter accounts (@96TruWarierQB, @ThugRaider37 and the black sheep of them all, @Basketball_Ron) with no immediately discernible differences. When SI.com recently approached him for a normal, run-of-the-mill interview, he unilaterally staged an elaborate, impromptu photo shoot complete with a camera crew and a 23-year-old Turkish model he had recently met in a hotel lobby. And, despite being otherwise good-natured, he started arguably the most infamous brawl in sports history, the Pacers-Pistons melee in 2004.

4. Dana White

If you're reading this list and you don't know who White is, I'm afraid you're sitting on the wrong end of the demographic curve. You may not like White's product (mixed martial arts) and you may not like the man himself, but you should be acutely aware of him for the simple reason that his UFC has become mainstream. White stands at the fore as an active general, someone who is as brilliant at marketing his sport as he is abrasive. He curses. He picks fights. He launches over the line, as when he employed YouTube to go off on a sportswriter he didn't like by using homophobic slurs. (He later apologized, sort of.) It's impressive that White's and the UFC's success comes in spite of that -- or, perhaps, partially because of it, these days.

5. Jose Canseco

No one believed him, predictably. Who would? Here was the guy who had a string of embarrassingly public problems throughout his life, financial and domestic. In October 2008, he'd be detained by immigration officials at the San Diego border for attempting to bring in a fertility drug from Mexico. In the span of one year, he would step into the ring against the likes of Danny Bonaduce (it was a majority draw) and 7-foot-2 MMA fighter Hong Man Choi (Canseco lost by submission). But in the end, it turns out, Canseco really did know drugs. He said the baseball star who didn't use PEDs was the exception, not the rule. He named Jason Giambi, Rafael Palmeiro, Mark McGwire, Miguel Tejada, Alex Rodriguez and Manny Ramirez, among others, as users. And so Canseco became baseball's Oracle of Delphi. The truth works in mysterious ways.

6. John Daly

He is at once the common man and completely unrelatable. He is thrice-divorced. He has named Jack Daniels as his biggest demon. He is a victim of his own addiction to gambling (to the tune of $50 million to $60 million over 12 years, he has guessed). He once teed off of a Bud Light tall boy at a pro-am tournament. He shot a 74 the day after his wife left scratch marks up and down his face. He was once discovered by police while passed out at Hooters, which incidentally once sponsored him (they no longer sponsor him). He is literally a background vocalist on a Kid Rock song.

7. Terrell Owens

Overexposure is an understatement. Whether it was spiking the ball off of the star in Texas Stadium (as a Niner), or lifting weights before the media on his front yard in New Jersey, or starring in an eponymous VH1 reality show, or playing for the Adirondack Wildcats of the U.S. Basketball League, or being hospitalized after ingesting pills as a Cowboy (he said it was an allergic reaction), or pulling a Sharpie out of his sneaker to celebrate a touchdown, or weeping at a press conference to defend the honor of Tony Romo, Owens seems to know exactly what we want: far, far, less of T.O. And thus we only get more.

8. Curt Schilling

You may not like Schilling: He's loud, he's blunt and he has mastered the Internet and the powers of his own celebrity as well as any other athlete this decade. His oft-updated personal Web site, 38Pitches.com, is a prime example of an athlete cutting out the middle man (read: journalists and flacks). Indeed, contrary to all P.R. conventional wisdom, he posts to the Sons of Sam Horn Red Sox message board. He is openly political and has campaigned for George W. Bush and John McCain. He was a hell of a postseason pitcher who, with his bloody sock, dramatically helped end the Red Sox's lifetime of futility. He is obsessed with online computer games like World of Warcraft and EverQuest. There is something, in other words, for most everyone to dislike.

9. Gilbert Arenas

Before the Twitter craze, before Yardbarker.com, before athletes and the Internet became synonymous, there was Arenas and his blog in October 2006. Sure, he's plenty good on the court -- when healthy -- but his Web site is what enabled fans worldwide to sample a taste of what former Wizards coach Eddie Jordan dubbed Gilbertology. That's the only term, really, to describe the man who once showered in shoes and full uniform during halftime of a game against the Warriors; who once dreamed up a commercial that involved a girl getting clotheslined by a kid in a wheelchair; who often prefers sleeping on a couch to a bed; who used to yell "Hibachi!" while shooting; who randomly joined a layup line of Elvis impersonators dunking off a trampoline during the 2007 All-Star Game (Shaq dared him, naturally).

10. Mike Tyson For all the crackling electricity of Tyson in the ring -- even today, it is virtually impossible to stumble upon an old fight of his and change the channel -- future generations will probably remember him for his exploits out of it. This is a shame, given how unbelievable he was in the squared circle, but wholly understandable. Simply witness director James Toback's recent Tyson documentary for a primer. Or plumb the depths of YouTube. You'll find a man-child whose malaprops are both hilarious and, knowing what we know about Tyson now, ultimately sad.

11. Ozzie Guillen

To watch Guillen on live TV as a talking head during the 2009 World Series was to see a besuited man as comfortable as a caged raccoon. Without the ability to unleash a torrid stream of profanity, after all, it was hard to identify the head as Guillen's in the first place. Consider a typical pregame tirade, from 2008: "We won it a couple years ago, and we're horse[bleep]. The Cubs haven't won in [100] years, and they're the [bleeping] best. [Bleep] it, we're good. [Bleep] everybody. We're horse[bleep], and we're going to be horse[bleep] the rest of our lives, no matter how many World Series we win. We are the [bleep] of Chicago. We're the Chicago [bleep]. We have the worst owner [Jerry Reinsdorf]. The guy's got seven [bleeping] rings, and he's the [bleeping] horse[bleep] owner." Indeed.

12. Bill Belichick

A personality doesn't need to be loud to be outsized, and Belichick -- perhaps this decade's most successful coach -- is quiet. He regularly renders a mockery of press conferences. He has made a hooded sweatshirt with cutoff sleeves into an iconic fashion statement. He was embroiled in a cheating scandal. Like the NFL's Darth Vader, he is still feared by everyone in the league. He is, in some ways, the anti-Muhammad Ali: He intimidates without soliloquoy, maybe even because he says so very little. There is an air of mystery always around him. He has a right-hand man with the Patriots (Ernie Adams) whom people know very little about. He seldom smiles. And he always goes for the throat. That's like Darth Vader, too.

13. Chad Ochocinco

There are wide receivers who are divas, and then there are wide receivers who decide to legally change their name to an inaccurate Spanish translation of their jersey number. But that, in sum, is why we love and hate Ochocinco. (As we all know, eighty-five is ochenta y cinco.) In the words of Charlie Murphy: Ochocinco is a habitual line-stepper. He'll feud with you on Twitter. He'll go on ESPN 2's First Take to debate Skip Bayless (the subject, naturally, was himself). He'll mock up a Hall of Fame jacket and wear it during a touchdown celebration. In fact, as NFL fines go, there's a new number we should all be familiar with: ochenta y cinco mil ($85,000).

14. Bobby Knight

Start with the chair, which defined Knight well into the '00s. It flew way back in 1985 -- a protest of a referee's call in a game versus Purdue -- but furniture is still how we remember Knight. Not so much for the three NCAA titles at Indiana, but for all the fury that eventually forced him out of Bloomington and into the national consciousness. He's a caricature in that way, which makes his recent public-relations rebirth as a commentator on ESPN so startling.

15. Lance Armstrong

Hate him or love him (a rift that often seems to fall along the Atlantic Ocean), Armstrong is not only one of the most decorated athletes in the world but also one of the most outspoken. Beyond vehemently denying accusations of doping, the seven-time Tour de France winner has used his celebrity to create Livestrong, a booming philanthropic brand that expects to raise more than $40 million this year. (In the meantime? He's more than happy to put his entire family on Twitter.)

16. Stephon Marbury

There was the face tattoo as well as the constant Ustream'ing, where he'd respond to viewers' questions, talk about how he saw Jesus in the shower the other day and eat vaseline (not in that order). With Marbury, there are so many reasons to put him on this list that you begin to wonder if it's all real. Apparently, it is. But even if Marbury is Andy Kaufman with a line of affordable sneakers and athletic wear, it doesn't make it any less unreal.

17. Floyd Mayweather

Say what you will about his defensive wizardry in the ring; Mayweather Jr. lives his promotional life on the offensive. Most everything about the man is fiscal exaggeration: the Vegas mansion, the lifestyle, the nickname (yes, Money). Of course, there are other issues (confiscated guns and shootings involving his friends, for instance); and hey, if the IRS has anything to say about it, maybe all that braggadocio isn't rooted in sound financials, after all. But caricature is exactly what boxing not only thrives on but also needs.

18. Danica Patrick

Her personality is outsized enough to be the first woman to win an IndyCar race. But Patrick has done more. She's posed in the SI Swimsuit issue. She's hawked everything from Secret deodorant to GoDaddy.com, and been in a Jay-Z video. The voice works, too: She told SI's Dan Patrick last June that taking steroids isn't cheating "if nobody finds out." Danica later called it a "bad joke." But for a driver who's also not afraid to get into on-track tiffs (ask Milka Duno), there's another term for it: ballsy.

19. Ricky Williams

Yes, the Dolphins' running back and former University of Texas star used to smoke marijuana. But that's not what warrants him a slot on this list -- or differentiates him from so many other athletes. Instead it's his singular honesty about one fact: Football does not define him. He may be an undisputed spaceball (he did wear a wedding dress on the cover of ESPN The Magazine), but the way he calmly describes his otherwise odd pursuits -- the study of yoga, massage therapy and holistic medicine, for example -- makes him startlingly refreshing.

20. Rasheed Wallace

Naming one's sports blog is no light task, so it's telling indeed that two notable ones -- Ball Don't Lie and Both Teams Played Hard -- so honor the menacing, quotable subversion of the man who holds the NBA's single-season record for technical fouls. The latter comes from the time 'Sheed, then in Portland, answered that very phrase to every question in a postgame press conference. The former is a statement of philosophy that comes from the time ... well, just watch.

***

Honorable Mention: Mark Cuban, Peyton Manning, Jeremy Roenick, Hope Solo, Serena Williams

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