Apparently Ben Stiller almost played Remy Thompson, a hot dog vendor hell-bent on ruining Mike Piazza's life. The unused script, which you can read all about here, sounds weirdly great, like a tamer, baseball-themed Being John Malkovich:
Having given up on baseball, Remy is now a 30-something sausage vendor who's elated to open up his own hot dog restaurant at Dodger Stadium, only to have Mike Piazza transferred there and his restaurant shut down as a result of the team spending so much money to get Piazza. Remy then moves and spends several years opening a restaurant at The Mets' Shea Stadium, only to have the same thing happen. "At that moment," he explains, "I decided to dedicate the rest of my existence to ruining the life of Mike Piazza."
Of course, this premise seems totally outlandish now, as the Mets would never have enough money to afford a hot dog vendor in the first place.