I mean, if your character is blind, that sort of makes you immune to the gaze of a basilisk, medusa, and possibly the charming ability of vampires. But it pretty much also means you're not going dungeon delving, so what's the point? I suppose you could play a blind linkboy or something who has memorized a particular path; wouldn't need to waste torches unless you're walking with someone.
If you're playing in a supers game and can be Daredevil, being blind isn't even an inconvenience, it's just a feature. Blindness is a -50 in GURPS, and even then that seems pretty underpriced, but if you have "Eyes don't work, but I can basically visualize the world in greater detail than any normal human", that's a -1 Quick and probably 20-30 points of Advantages. Makes sense for Daredevil, but if you just have the -50 disadvantage, you better be the best Bard in existence.
RE: "cool uses for disabilities", how would that even work? I know a guy who got his leg blown off in Afghanistan, it was funny as hell when he'd pull off the prosthetic and freak someone out. I don't think that has much of a purpose in the context of an RPG, though.