Programming. Realtime computer graphics. Demoscene. Game development. Stuff.
Geoff Zatkin's essay
A must read article for any game developer wannabe here:
Your industry heroes work like dogs too. Ask a Blizzard employee what their "core" hours were for the last year+ before WoW launched. Or a Bungie employee leading up to Halo shipping. And those are the lucky ones. For every studio that turned out a brilliant game, multiple other teams of equally cool people ended up wasting years of their lives working on games that never saw the light of day, came out stillborn or got pushed out early and died an ignominious screaming bug-filled death.
How sad, and how true...