My brother (matstc) and I had about a week of free time recently and we decided to build a few websites along the concept of "Hot or Not" (that is, a simple interactive rating site):
www.hugamovie.com
www.hugacity.com
www.hugamusic.com
www.huganoodle.com
We're aware it's not rocket science and we're not going to get rich with it. But we had fun in the process and it allowed us to experiment with a few toys: Rails, Google AdSense, Amazon associates. Our 4 sites have been running for a week now, and we would be interested to get your feedback on about anything related to those sites.
Here for starters: Do you like the simple design? Any suggestions to maximize the revenue? Is it a good choice to use Google AdSense on these kinds of sites? What's your experience with being an Amazon associate (our ads in the bottom-left corner)?
Automate the process of doing A/B studies. In other words, make it easy for you to test a different layout against the existing one. 10-20% of your users should see the test design. This will give you concreate data on how your changes improve things like stickiness and ad clicks. Keep what works. Rinse, repeat, get rich :)