I think the last time we had this topic, I answered NOISES OFF, and I see no need to change that. I also saw the film of NOISES OFF again recently, and I enjoyed it SO much more than when it was originally released. Maybe it was seeing Christopher Reeve so physically fit in it, but for whatever the reason, it worked a lot better as a film than I remembered it. I still prefer the stage version, of course,
I'm not sure it qualifies as a farce, but I also loved BLACK COMEDY on stage. And LEND ME A TENOR is very, very funny.
FORUM ranks at the top of the heap (a NY, NY reference) of musical farces. I wish someone would remake the film of it, even if it's a videotape of a professional stage version done in the manner of INTO THE WOODS or SUNDAY IN THE PARK.
Yep, THE PRODUCERS and ARSENIC AND OLD LACE are pretty hard to beat. DUCK SOUP right up there, and the hotel room sequence in THE COCOANUTS is very funny, too.