I threatened, a while ago, to describe why I think Martin is a cool character. And now it's late, and I'm tired, and I need to write something. So I've compiled a list. Well, the rest of the list.
He's not annoying in combat. I mostly credit his use of ranged magic attacks for this. (If only all NPCs were so skilled.) He doesn't hit me, he doesn't get in my way, and most of all . . .
He doesn't die. Except for a couple of plot critical points, he can't. Now, sure, this makes the game easier, but it also makes it a lot less annoying, because you don't have to worry about him wandering off and getting himself into trouble. Which is good, because he wanders off to fight bandits more or less constantly.
As an added bonus, his immunity to death means that, if for some reason he ends up very angry with you, you can just knock him out. When he comes to, he'll have no memory of whatever it is you did that ticked him off. There is endless entertainment value in this phenomena.
In general, though: He does things. Granted, sometimes he does annoying things. (Dammit, Martin, I just need one point of blade to level up!) But for the most of the game, he's actually kind of useful. He tells you a lot of interesting things. He's as involved in the whole "saving the world" gig as you are. But what he does, he does without upstaging you. In a major way . . .
He helps you be cool. He's constantly coming up with crazy plans that, basically, only you can pull off. Because no one else is awesome enough. And he never doubts that you can do it. Every conversation you have with the guy reaffirms your awesomeness.
And, of course: He's kind of geeky. I'm serious. There's no other way to describe someone who's constantly coming up with bizarre schemes, covers a table with books, gets another table so he can cover it with books, and responds to you showing up with an incredibly evil artifact by saying, "You should give it to me, because it's, uh, dangerous. Yeah."
Why does this make Martin cool? Because the only people who care whether he's cool are geeks. RPG geeks. The kind of people who actually watch video game cut scenes. The kind of people who combine English major style literary analysis to video games. Even if video games are going mainstream, RPGs are still played by some pretty geeky people.
I'll probably come up with some more reasons, eventually, but those are the basic reasons why I think Martin is cool. Besides the scowling, anyway.