This thread brings up some really important points about testing Google Adsense ads against potientially higher affiliate income. It also reminds affiliates not to forget sites they have already built (assets). dazzlindonna had this to say over at SEOchat :

One of my very first websites was a small… site that existed to sell an affiliate software…Over time, I created more sites and eventually kind of forgot about that site. At some point during that time, I added Adsense ads to the site… Yesterday, on a whim, I took the adsense ads off of the site. Guess what? I’ve made two affiliate sales today (which is about $100 commission). I hadn’t made a single sale in at least a year, and one day after removing adsense, I make two sales… Hmmmm…

Read the important tips here and participate in the discussion. Adsense vs. Affiliate Programs