Discrete math is what tends to be useful in programming. I have a couple years experience as a developer but I guess I'd say I'm sort of in the same boat as you where I am trying to gain a more solid grounding in mathematics to hopefully eventually move away from doing CRUD style development. I got a book off Amazon called "Discrete and Combinatorial Mathematics" that was really cheap (the total with shipping was like $4-5), so maybe check that out.