I second all those points. They sum up my reasons for programming well, but I'd perhaps add a fifth:

• I'm compulsive

...by which I mean my brain will happily stay in a code-run-debug loop for long periods. I feel compelled to figure out the next thing! Programming is one task that rewards that particular character trait.

Rands is funny. (Update: hehe, I guess TimToady was in the crowd... and then Rands borked the 'fixed' regex)