Iron Maiden. Because they're British. Seriously though, watch some of the extra stuff from Flight 666 on YouTube, it's f*cking hilarious, they're like a modern-day Monty Python. Bruce Dickinson should take up comedy if Maiden ever disbands. Steve Harris is the only one that never really does anything exceptionally hilarious, since he's kinda shy and doesn't usually say much, but that's okay, because Steve is god.
Rammstein seems to have a good sense of humor too, especially Paul. Their 'behind the scenes' stuff always gets a laugh out of me, and their live shows are always...interesting. lol.