[mhd]

It's a bit like learning a language, you'd need some almost immediate application to make it past the first steps of a book or course (and/or make that gained knowledge stick). And while it's easy enough to travel to some country where they speak a language you just learned, that's often harder when it comes to mathematics and IT.

3D maths and game development worked out somewhat in the past (I forgot most of it though, and as that was the DOS days it wasn't really more than high school level geometry). But I doubt that I could find enough real noticeable application for e.g. category theory.

(Just being the basis for something often isn't enough. You don't need to know much about physics to hop on a trampoline.)

[Davertron]

I was going to say, a lot of the Math I learned in High School and then never applied to anything I re-learned more recently when I started mucking around with computer graphics and game dev (especially trig, matrices, vector math, etc.)

I'd love it if people had suggestions for other engaging ways to apply math while programming!

[bonobo3000]

I highly recommend Jeremy Kun's blog - Math and Programming (http://jeremykun.com/). His posts are always awesome.