Far, FAR too many to list.
Just about all of the above.
OldJeff has it nailed with the "presence", too. Take Jeff Goldblum. HOTTTTTTTTTTT. He looks like one of the biggest nerds on the planet, and at the same time he just oozes sexuality.
What sane woman wouldn't want to spend an evening by the fire with Sean Connery? Purrrrrrrrr
Basically any man with long hair will get me going. Add in a nice poet's shirt and a dagger or sword hanging off of their hip and I'm mush. Give them a close-cut beard and I'm nothing but a puddle on the floor.
But then again, the sexy, quiet confidence of a clean-cut guy gets me most of the time too. Ben Affleck is an example. The actor who plays Gil Grissom on CSI, YUMMY.
Like I said, just too many to list! Men are sexy, no getting around it.
And women are naturally amazing, curvaceous, soft sexy irresistable creatures... thank god I'm a woman, I can appreciate other hot women without anyone giving it a second thought :P