Granola bars are a must-have. And not the kind loaded with caramel, chocolate chips, marshmellows, etc. I like the Nature Valley stuff because it isn't loaded with sugar. Hate to get a cramp on a hike/mountain biking expedition from sugar withdrawal.
As for other stuff:
Boil-in-the-bag rice (Zatarain's dirty rice and beans rocks!)
Salt tabs. Old Green Beret I know taught me this one. You can hydrate all you want, but replacing salt is vital.
REI and other major camping supply stores sell tons of ready-to-eat meals for this kinda stuff. A quick search of REI's site gave 125 different entrees alone!
Misadventures of a Crazed Kitchen Pirate
"Steve is the prototypical cool American male. Y'know, I'm talking about Steve McGarrett, alright? Steve Austin, Steve McQueen. Y'know, he's the guy on his horse, the guy alone. He has his own code of honor, his own code of ethics, his own rules of living, man. He never, ever tries to impress the women but he always gets the girl."