I like xkcd and Terry Pratchett (though more for the ideas and attitude than the humor-- the humor is apt to be pretty stereotyped).

I like good single puns, but have lost a good bit of my taste for long series of puns on a subject. I blame Anthony and Robinson.

I like one-liners and paradoxical humor.

Sometimes I like slapstick. I thought the movie Noises Off (screwball comedy leaks from a play into the lives of the cast) was extremely funny. There's a consensus that a good stage production is twice as funny, which is hard for me to imagine. In any case, as soon as a cactus showed up, it was pleasing to know that someone would sit on it.

I thought the stuff in early HPMOR where Harry was rolling over the adults was extremely funny. Other things were funny, too, but that's what comes to mind as a theme.