You are probably been targeted by Google Adsense smart pricing tactic. That means you have loads of clicks but nobody buying anything from your clicks. So Google put your account under smart pricing and you make less money. There is not much you can do about it just make sure the people clicking on your site is actually quality traffic.
If you like to privacy to be just that Private and you are sharing your internet and computer with family, work or an internet café and you are not a computer geek. Then you should consider software that Clear History of your visited to that site or looked at that movie. Sure you can delete the cash and wipe the history but there are so many more places you have to go and if you not really good with internet it is impossible for you to find all the places. There is an also a question of time, you will save loads of time using software instead of doing it manually.
Finally Word Press the free dominating blog system have released it update to Word Press 2.1 called Ella after the great Jazz singer. But do not be so quick to update if you have loads of plug ins and add on. I did the mistake by updating to quick and now my plug in has not been updated. Some have followed but most of them are still on 2.06 and they do not work on the new versions. He new version works like a dream and is faster but as I said wait until the plug ins you like so much have updated as well.