Bishop has one of the coolest powers in the entire comics universe: He can rechannel energy; which means that if someone shoot energy blasts at him not only does it not hurt him, he absorbs it and can shoot it back at the enemy! Which is probably the best power to have when fighting other super-powered people, because about half of them seem to have energy powers. Of course, if they're shooting real bullets instead of plasma stuff from guns, then he's in trouble. I read about Bishop taking out a plasma-shooting tank after it had shot him, using its own energy. Now that's power!
Also, his future is totally cool. Yes, I know it's bad out there, but a "mutants policing mutants" through the XSE (Xavier's Security Enforcers) is awesome. And the wearing of the X-Brand on the face thing as a badge of honor is neat. I absolutly love the Bishop Limited Series, in which that whole concept of what it means to be in the XSE is explained, along with Bishop and his sister Shard's history/future.
A really good Bishop quote, which just sums up the attitute of responsibility he carries: Bishop to Archangel: "Being an X-Man isn't something you can walk away from." (Uncanny X-Men #331) 
