Slghtly unrelated to hacking..
when you guys think of a start up/web app, do you think you want to make something that will change the world, or something that will make you rich?
That way, if it goes nowhere (which is likely), I haven't wasted my time, since I now have a useful tool.
if you're the type of person who wants to change the world, but can only come up with an idea that makes you rich, that money can be used as a tool to help you change the world.
if you want to get rich, even a "change-the-world" type of idea will turn inward into something that will get you rich (potentially ruining it in the process, though).
Mozilla, Miro, Wikipedia....the list goes on. If it was inverse - i.e. the number of non-profits outweighed the number of for-profits - I am quite certain you'd see a bigger change in the world.