This article was a very interesting with some insight into the Android Market. Basically, this indie Android developer has published 6 free applications and is making more than $1,000.00 per month off of advertisements.

None of my apps has been ever promoted in Top of Android Market

I am providing only free apps (mostly due of Android Market limitations)

Even if I would be able to sell apps I would not use it as main income source… (I believe that you still can make more from ads…)

via Android Developer Income Report.

I think there is an interesting experiment here. I am going to attempt this. Making super simple novelty apps (very low barrier to entry) that are free with ad support. I know this just further convolutes the crap that is the Android Market, but it would be fun to test.

If I actually end up doing this, I will publish some results here.