So what if it may well be a ploy by Mark Zuckerberg and co. to develop a sophisticated facial recognition algorithm that can track age progression, the #10YearChallenge is still fun.
So, we thought we'd bring it into the footballing world, and take a #TBT look at the lineups of all the "elite" clubs across Europe from 2009, and compare them to now.
As far as I can work out, the date of this throwback picture is arbitrary, so that's what we've gone with here, although a common theme/easy find seems to be the Champions League quarter finals.
2009 Starting XI: Van der Sar; O'Shea, Ferdinand, Vidic, Evra; Giggs, Carrick, Anderson; Rooney, Berbatov, Ronaldo.
2019 Starting XI: De Gea; Young, Lindelof, Jones, Shaw; Matic, Herrera, Pogba, Lingard; Martial, Rashford.
That first lineup is taken from the away leg of the 2009 quarter final with Porto, the second from United's last clash with Tottenham, and what strikes you right away is the defensive discrepancies. The first rearguard is Hall of Fame level. The second is, well, shameful.
The midfield is pretty damning as well, especially when you consider Paul Scholes replaced Anderson late on. The fact that United have only been able to produce such a picture three times since, the most recent of which was 2014, tells you all you need to know.
2009 Starting XI: Buffon; Grygera, Mellberg, Chiellini, Molinaro; Tiago, Marchisio, Nedved; Iaquinta, Del Piero, Trezeguet.
2019 Starting XI: Szczesny; Cancelo, Bonucci, Chiellini, Sandro; Bentancur, Pjanic, Matuidi; Costa, Dybala, Ronaldo.
Taken from the Champions League round of 16 this time, because the Old Lady couldn't get past Chelsea to make it to the quarters, what a fascinating team that is. Everlasting legends are placed alongside genuine nobodies. The back four consists of a Fulham reject, an Aston Villa stalwart, a Frosinone player and GIORGIO CHIELLINI.
Pavel Nedved is being forced to grace the same pitch as TIAGO. The same goes for Alessandro Del Piero and David Trezeguet with Vincenzo Iaquinta. Obviously, today's team is far more imposing and well-rounded. But is it more fun? Probably not.
2009 Starting XI: Cech; Bosingwa, Terry, Alex, Ashley Cole; Mikel, Ballack, Essien, Lampard; Drogba, Anelka.
Subs Not Used: Hilario, Malouda, Deco, Kalou, Mancienne.
2019 Starting XI: Kepa; Azpilicueta, Rudiger, Luiz, Alonso; Kante, Jorginho, Kovacic; Pedro, Hazard, Willian
Speaking of that Juventus tie, we thought we'd opt for Chelsea's XI from that very game, even though they did indeed make the quarters. Because it's such a fascinatingly different team. I mean look at those two frontlines. They're polar opposites.
That throwback midfield is surely one of the most industrious ever seen. The defence is underwhelming, considering what it could've been, but still foreboding. Jose Bosingwa definitely hasn't aged well. But, to be fair, neither has Marcos Alonso.
2009 Starting XI: Butt; Lell, Lucio, Demichelis, Lahm; Sosa, Van Bommel, Ottl, Ze Roberto; Ribery, Toni.
2019* Starting XI: Neuer; Rafinha, Sule, Boateng, Alaba; Martinez; Muller, Kimmich, Thiago, Ribery; Lewandowski.
First of all, hats off to this unconventional team photo - it's the only one I could find. It comes from the second leg of Bayern's quarter final with Barcelona, after they'd been blown away 4-0 at the Nou Camp.
In my eyes, this one of the most fascinating comparisons, because it shows two teams on the wane. Two teams at the end of their cycle. Of course, in between them, a new team was born, and spectacular heights were hit, but in isolation, both of these sides are past their best, and in need of rebuilding.
*DISCLAIMER - this is actually from 2018, because the Bavarians are yet to turn out in 2019. I'm sorry for misleading you.
2009 Starting XI: Given; Richards, Onuoha, Dunne, Bridge; Zabaleta, Kompany, Ireland, Elano; Robinho, Caicedo.
2019 Starting XI: Ederson; Walker, Stones, Laporte, Danilo; B. Silva, Fernandinho, D. Silva; Sterling, Jesus, Sane.
Hilarious. This is from the 2009 quarter final second leg against Hamburg in the UEFA Cup, when City admirably crashed out 4-3 on aggregate despite a 2-1 victory.
So much of this is funny, but if I had to rank them, it would be: 3) The centre back pairing of Nedum Onuoha and Richard Dunne 2) Pablo Zabaleta and Vincent Kompany in the slowest midfield of all time 1) Dunne being sent off, obviously, and a Guardian minute-by-minute report admitting: "The only surprise is that it took that long."
2009 Starting XI: Valdes; Dani Alves, Marquez, Pique, Puyol; Xavi, Yaya Toure, Iniesta; Messi, Eto'o, Henry.
2019 Starting XI: Ter Stegen; Roberto, Pique, Lenglet, Alba; Rakitic, Busquets, Arthur; Messi, Suarez, Coutinho.
The 11 who trounced Bayern 4-0, and would go on to win the competition outright. What a hallowed group. Gerard Pique and Lionel Messi are the only surviving members from the starting lineup, though Sergio Busquets was a late substitute for Yaya Toure.
Who came on for Samuel Eto'o in the 89th minute, you ask? Bojan Krkic. Obviously.
2009 Starting XI: Reina; Arbeloa, Skrtel, Carragher, Aurelio; Alonso (Lucas 60), Mascherano, Gerrard; Babel, Kuyt, Torres.
2019 Starting XI: Alisson; Alexander-Arnold, Fabinho, Van Dijk, Robertson; Wijnaldum, Henderson; Shaqiri, Firmino, Mane; Salah.
This is taken from the Last 16 home leg against Real Madrid, when the Reds blew Los Blancos away 4-0 to progress by five clear goals. Though Steven Gerrard got a brace, it is mostly remembered as a Fernando Torres masterclass, after the Spaniard returned from injury to torment his eternal rivals.
It's a fairly formidable lineup to be fair, and they would go on to valiantly lose to Chelsea in a historic quarter final tie culminating in a 4-4 draw. However, they'd already won the competition that year when they brought on Jay Spearing for Gerrard in the 74th minute of the 4-0 thumping of Real.
2009 Starting XI: Casillas; Ramos, Cannavaro (Van der Vaart 64), Pepe, Heinze; Robben, Lassana Diarra, Gago; Sneijder, Raul, Higuain.
2019 Starting XI: Courtois; Varane, Ramos, Nacho; Carvajal, Casemiro, Valverde, Reguilon; Modric, Benzema, Vinicius.
I imagine all you could think about when reading that Liverpool section was: "What was the Real Madrid team that lost 4-0 at Anfield?!?!". Well, take it in.
Not bad, is it? In fact, every single one of this players is pretty much exceptional, except for maybe Gago, Diarra and Heinze. The problem was, at least three of them - Wesley Sneijder, Arjen Robben and Fabio Cannavaro - were exceptional the following season with different teams. Shame.
2019 Starting XI: Leno; Mustafi, Sokratis, Koscielny; Maitland-Niles, Guendouzi, Xhaka, Kolasinac; Aubameyang, Lacazettte, Iwobi.
Ahh, the Champions League. Do you remember it, Arsenal fans? Can you even fathom it any more? It's a prestigious competition which you repeatedly went out in the Last 16 in, until you eventually just stopped trying to be in it altogether.
But this team is taken from those dizzying times when you would reach the quarters, hell, even semis. This lineup in particular is from a 3-0 win over Robert Pires and Villarreal. It was so comfortable, the Gunners brought on Nicklas Bendtner for the last seven minutes. Even Abou Diaby got a 13-minute cameo, during which he almost certainly got injured.
2009 Starting XI: Gomes; Gunter, Chimbonda, Huddlestone, Gilberto; Giovani, Palacios, O'Hara, Bale; Campbell, Obika.
2019 Starting XI: Lloris; Trippier, Alderweireld, Vertonghen, Davies; Winks, Sissoko, Eriksen, Alli; Kane, Son.
Yikes. I couldn't find a team photo of this UEFA Cup round 32 clash with Shakhtar Donetsk, so Harry Redknapp gesticulating will have to do. To be fair, I'm not surprised no one took a photo of that lineup. Look at it. Just look at it.
Suffice to say, Spurs crashed out 3-1 on aggregate, despite the inspired substitutions of John Bostock and Dean Parrett (?!?!?!?!). At least they had Bale. Huddleston at centre back, though. Quite the price to pay.