Owner of this website reportedly earned $14,436.45 in May 2005. As you can see from the above screenshot he uses quite interesting technique of displaying AdSense ads (putting a small camera pic at the left side of the ad). Doing so will make the ads appear as suggested link and look less Google Ad, as a result the clicks on the links will be icreased. Because people tend to click more on the suggested links than on ads. I don’t know if it violates the Rules and Regulations of AdSense Program. If it does not then you might want to try it on your own website.
Something similar is being discussed at http://www.webmasterworld.com/forum89/7961.htm
One more link regarding this topic http://forums.digitalpoint.com/showthread.php?t=17104