Nicholas Andre was played by former Saturday Night Live cast member Charles Rocket (from the 1980-1981 season, which was considered one of SNL's many low points). What's funny is that Jim Carrey auditioned to be on the 1980-1981 season and was passed up in favor of Rocket.
Then-NHL star Cam Neely is Seabass.
One Steve Limit: Averted out-of-universe; actress Karen Duffy oddly played two characters named Shay that year, in this film and Blank Check.
Averted also with Jeff Daniels, who played two characters named Harry in 1994, the other being in Speed.
Playing Against Type: Jeff Daniels was not a comedic actor before he made this film, but the Farrelly Brothers convinced the studio to let them have Daniels in their movie when they watched ''Something Wild".
Romance on the Set: Jim Carrey and Lauren Holly married after meeting on this film, but it lasted less than a year.
Sequel Gap: Dumb and Dumber To comes out 20 years later. The setting apparently has Lloyd spending all this time faking insanity to the point of catatonia just to prank Harry.
Throw It In: Jim Carrey threw in quite a bit, like "We landed on the moon!" and even "the most annoying sound in the world" (with the latter, you can clearly see Jeff Daniels and Mike Starr trying to hold it together, bracing for whatever Carrey was about to do; Daniels fails and loses his shit right before it cuts to a close-up of Starr).