Here's one example: Ten years ago, there was an episode of Animaniacs that used a variation on a gag from Hellzapoppin (Amid Amidi will no doubt consider this further proof that Animaniacs was an unoriginal piece of hackwork). I speculated online that the writers must have been paying homage to Hellzapoppin. And in response, I was told that, yes, one of the producers brought in a print of Hellzapoppin to show the writers the kind of humor he wanted them to go for, and the writers fell in love with it.
Now, Hellzapoppin is not a "great" comedy by most definitions of the term. Olsen and Johnson had very little individuality as performers, never really developed strong characterizations for themselves (that's part of the reason why they didn't last long in films), and the big laughs tend to come from their reactions to the crazy people who pop in and out. The studio insisted that the movie have a plot (the stage show was a revue), and the plot drags down the comedy, as the stars themselves point out. Most of the really inspired stuff happens in the first ten minutes; indeed, some admirers of the film would just as soon lose everything that happens after those first ten minutes, when the story kicks in and the picture gets more normal. And Olsen and Johnson were heavily reliant on old, old, old jokes; the New York critics loathed the stage version of Hellzapoppin for daring to pollute the Broadway stage with the leftovers of Vaudeville and Burlesque.
But Olsen and Johnson's films, the best moments in them anyway, can be pretty stunning. In part because they actually tried to do movie comedy, comedy that would make fun of the conventions of movies: talking to the projectionist, arguing with the director, gunning the romantic couple down with a machine gun (that's the end of Crazy House, a favorite of Quentin Tarantino). Unlike the Marx Brothers and other comedy teams who basically just brought their stage act to the screen, Olsen and Johnson are aware that they're in a new medium and they're out to demolish it. But they love it too; in fact, they -- or their writers -- are movie buffs, and their movies brim with references to other movies at a time when this sort of thing was still relatively new. Who else but O&J, in Hellzapoppin, would spoil the ending of Citizen Kane just after that movie had come out? The only other films of the era that have so many references to other movies are the Warner Brothers cartoons (and, as it happens, the only other movie of that era with a Citizen Kane reference is the WB cartoon "Coal Black and de Sebben Dwarves").
I think my favorite gag in Hellzapoppin, apart from the Kane joke, is the variation on the old "That's good, that's bad" staple:
OLSEN (speaking into a telephone): That's good... that's good... that's bad... that's good....that's bad....
JOHNSON: What's the matter? What are you doing?
OLSEN: I'm helping her sort a box of strawberries. That's bad... that's good...
Because of the rights problems, Hellzapoppin isn't on VHS or DVD, but if it turns up on TV, at least watch the first ten minutes or so. Your mind will be blown. Odd how comedians as gleefully lowbrow as Olsen and Johnson can sometimes come off as so sophisticated -- and hold up so well.
A longer article about Olsen and Johnson is here.