I'm going to go with Louis from Left 4 Dead. Nerdy, optimistic to the point of being occasionally irritating, and in spite of all my efforts to the contrary, will probably end up being a nebbish office-worker type.
Although I'm not black, so that probably buggers up the comparison a bit.
If that gorram Firefly MMO ever gets made, though, I'd love to compare myself to Wash. I don't collect Hawaiian shirts just because they're comfortable.