Hmmm...I couldn't really see myself doing any of them, but if I had to choose, I'd have to say:
Armand Assante (I have a thing for voices, and just....damn.)
Anthony Hopkins (I like him as the Doctor, but the cannibalism would have to go..Yeah, I know I'm going to get a crapload of smartass comments for that one

)
Val Kilmer (two words: Doc Holliday)
The guy who played Boromir in LOTR (but he'd have to BE Boromir--none of the LOTR guys really look good unless they're scraggly)
Mel Gibson (...I can't help myself. He's just so damned CUTE)
Honorable Mention:
Sean Connery (he can just read the phone book to me or something)
Sidhe