In the category of looking cool but being as dumb as they get Boba Fett wins hands down. He first appeared in The Empire Strikes Back (yes he did, forget that awful scene they stuck into A New Hope) alongside various other bounty hunters but stuck out a mile for his back chat to Vader and his awesome outfit.
The whole Sarlaac incident where Boba is just so inept and suffers the stupidity of falling into the monsters mouth just annoyed me so much. Back in '83 I had already decided he just escaped after everyone was gone, he was too cool to have gone out that way. Of course in later years his popularity brought around the whole 'oh it was always my intention that Boba escaped the Sarlaac' statements that comes out from Lucas and team and gave us the Fett family back story in the prequel films. Mentioning the prequels I will say that if my thoughts that Boba was a dumb son of a so and so his Father surely proved where he got his brains.