There's a scene in this movie where Dan Aykroyd, brought low in a social experiment of nature versus nurture, sits on a bus in a Santa Claus suit. He's drunk and foul looking and he had just failed to frame Eddie Murphy at a company Christmas party of his former employers in an attempt try to reclaim his previous life. At the party he had "procured" some food and booze. Now sitting on a bus he pulls a smoked salmon out of his coat and tries to eat it through his Santa Claus beard getting hair stuck in his mouth. It is one of the funniest and nastiest bits I have ever seen. Sure there's sicker gags out there on film but that beard is just a nasty, filthy looking beard and I'm not sure I'd wear it much less let it get stuck on food that I was trying to eat.
The film is one John Landis' last of his really funny comedies that he made. After this he made several mediocre comedies like Spies Like Us and Coming to America and more than a few done right disasters - Innocent Blood, Beverly Hills Cop III and The Stupids.
This is one of those rare comedies that has some insightful social commentary. It also has an ending that apparently makes perfect sense if you're a commodities broker. I've tried to follow it several times and I think I understand what's going on. Fortunately there are folks out that look into this sort of thing and have actually explained what happens.