Money. I hate to be so cliche but money is the absolute #1 driving force for everything I do / learn / work towards.
People say money can't buy happiness, and that may be true, but money can help buy life. Without money you can't see doctors, you can't receive cancer treatment, its more difficult to get a good education without money, it's difficult to do fun things without money.
Yes, we're programmers and you don't need to goto school to learn a language, but my kids may not necessarily be programmers. Hopefully they want to become doctors, or dentists, or lawyers or engineers. And those jobs require degrees and those degrees require money, sometimes, lots of it. Can they earn it on they're own and get school loans like everyone else? Absolutely - but if I can help them accomplish their goals, all the better.
Having my name known in some obscure group only known to programmers - meh. Walking into a room and people recognizing my face and coming up to talk to me? meh. Putting snow tires on a $250,000 sports car and driving around in a NY winter? hell yes - because I can and because I earned it.