Eddie Izzard... A man in high heels who can spend 2 hours in New York getting laughs by putting shit on americans without the audience realizing he's pulling the piss... that get's my vote.
"do you know there's other countries?"
Dylan Moran a close second. The progression of his shows is brilliant, directly proportional to the number of glasses of red he's gotten through. The Irish don't have much going for them but they are the funniest fuckers on the planet.
without the audience realizing he's pulling the piss...
+rep+1 for Louis CK. His "Why?" bit is one of the greatest of all time IMO.