I think rogues are awesome, though this is based primarily on a reading of the class and its powers, rather than seeing them in play. I also like the flavor of warlocks (especially fey and starlocks), and I really like the barbarian's rage powers. Monks (with their full disciplines) and avengers are cool, too. I think sorcerers fall kind of flat, though they are insanely good at spreading their striker damage over multiple targets.
But the best striker I've seen in action is a dragonborn ranger with the stormwarden PP, Scimitar Dance, and the Wintertouched/Lasting Frost/frost weapon combo.
I'd probably have to go two-blade ranger, rogue, and warlock (the warlock mainly because of their interesting status effects, mobility, and overall coolness), in that order.