In my case, it's all about getting into the computer science rather than "programming" per se. I love reading papers and articles related to the problems I'm solving and then working out if they'd help me. Taking sloppy O(n*n) algorithms I've bashed together and getting them down to O(n) - or whatever - is very fulfilling.

This might just make me weird though ;-) I guess I like to think I'm working towards actually making an academic contribution to the world one day, rather than just doing something to earn some money - that's a big driver for me in terms of life ambition.