Trivia: The 40-Year-Old Virgin
- Bilingual Bonus: The "Guatemalan love song" that Jane Lynch sings had Spanish-speaking audiences laughing. It's not a love song.
- Dawson Casting; 19 year old Kat Dennings as 16 year old Marla.
- Inverted with 23 year old Seth Rogen as Cal who is implied to be much older.
- Dyeing for Your Art: The chest-waxing scene? Yeah, one hundred percent real. Ouch. For the obvious reason, this was a one-take scene. In fact, at one point they almost ripped off Steve Carell's nipple, because they forgot the stuff that you're supposed to put on nipples to prevent them from being ripped off. You can also see his blood starting to bubble out, as noted in the commentary.
- Enforced Method Acting: See above.
- Hey, It's That Guy!:
- Real-Life Relative: Steve Carell's wife Nancy Walls plays the teen clinic sex counselor. Leslie Mann, who plays Nicky, is married to Judd Apatow.
- Star-Making Role: For Steve Carell.
- Throw It In: All of Andy's exclamations during the waxing scene were improvised by Steve Carell out of the real pain he was going through. Apatow kept separate lists for profane and non-profane ones, so they could mix and match as they pleased.