NOTE: Gaming topics have been moved to Tabletop Manifesto.
I recently acquired a copy of Munchkin and I feel compelled to say just how good it is.
It's good. It's a lot of good.
Even my wife, who isn't into gaming at all, likes playing it. It's a fast game (unless everyone plays dirty) and generally fun. A lot of that results from the silly names of the cards and items (The Kneepads of Allure, The Boots of Butt Kicking), and the rest comes from the rise and fall of fortunes. Just when success seems immanent any number of things can go horribly against you.
If you're looking for a game that only takes a few people to play and can be wrapped up in less than an hour then give it a go.