One of my sites is making average $1 a day. It's not a lot, but it pays off the hosting already. If I can boost traffic to 1000 times a day, I imagine that I could easily make $1000 a day.

The question is how to create quality traffic and content that covert visitor into buyer or click on the Ads. One trick I found is to offer quality content but not enough to give visitors all the answered they need. So they click on the ads.

Also, the Ad placement play an very important roles in terms of click through rate. Many people put the Ad at the bottom of the web page simply just don't convert.

That's my 2 cents.