Math for dummies

Howdy /book/, the last time I actually did any "serious" math work was back in high school and I'm running out of classes that I can use to avoid actually doing any, so instead of just taking a lower level math class and working my way up, I thought I'd brush up a bit instead of wasting money on an actual class.

tl;dr Does /book/ have any suggestions for teach yourself math books?

Michael Spivak - Calculus

The best calculus text around. Of course, it's not easy, but if you really want to understand calculus then you need to get into the nitty gritty stuff (this book is also a course in Analysis).