(Have we had this topic before?)
Gaila and the Sexyprise. For the same reasons, "if you'll pardon the Engineering parlance."
*Ahem* Anyway, there's Urban-McCoy and Nimoy-Spock, because they did such a great job at emulating the original actors' portrayals of the characters... Wait a sec.
There's also Simon Pegg's Scotty. Brilliant. Captain Pike as well. He kicked major tail. Aw hell, why bother? Everyone was great.