pewinternet.org
First, people are willing to pay for stuff that can be found for free. The difficulty in buying something online is about equal to pirating it, which means that a significant number of people are willing to support things they believe in. Why this is, I can't say.
Second, that there is a huge potential market for digital goods. There are a lot of people on the internet and distances don't matter, which means that you could have a huge customer base (65% of "a lot", to be exact).
Combine those together and I think the conclusion is that we're going to see a continued revival of "garage programmers" selling digital goods.