I'm usually not one for really old movies (though one of these days I'll have to check the classics like Citizen Kane for myself) but I like a fairly wide range of comedy when it comes to movies, TV shows and standup comedians and recently I've been watching a fair few Marx Brothers movies. I'm not sure they'd appeal to everyone especially since their comedy has its rootes in vaudeville (and thus is pretty dated by now) but at their best, the wordplay and schtick is pretty good. As musicians they were pretty talented as well.
If anyone wants to give them a look, I'd recommend Duck Soup, Room Service, Animal Crackers and Monkey Business, the first two especially.
As with a lot of old-time stuff, it's also kind of cool to see things that have been referenced by more modern shows and movies. The influence of Groucho Marx in some of Bugs Bunny's schtick is quite apparent (and at times, he/Mel Blanc does a flat out impersonation of Groucho), as well as in Alan Alda's portrayal of Hawkeye in M*A*S*H though it certainly fits the character as it's easy to imagine the character being a fan of Groucho's style. There's also a scene in Horse Feathers that I now recognise as being referenced in Return to Zork, when the fast-talking lighthouse keeper asks for the password, references "swordfish" and then reveals he's forgotten the password.
So yeah, if you're looking for something different and you've got an appreciation for old movies I'd recommend giving at least one of their films a look. I realise I could be creating a thread that could quickly sink to the bottom of Entertainment Talk but I'd be interested to know if there's anyone else who already finds them entertaining or would gain an appreciation for them after seeing a few of their films, as I have.