I will probably get some flames for this by some of you, but I confess I have fooled google before... I own 2 websites, which gets around 10,000 visits daily combined, the ads are very low paying so I used some some techniques so it displays other more high paying ads. My real ads only earn me around $2K a month, when I used this method, I got $7K a month! you see why I was so tempted? even if I get ban later, it would be worth it because of allthe extra $ im getting. anyway, this lasted for nearly a year, then I received an email from google. After reading all these comments on digitalpoint, I thought I was doomed, but to my surprise,the email only pointed out that my ads were not in compliance with their policy and gave me 2 days to fix it. I fixed it up, and they thanked me for cooperating Anyway, now I am earning all my money legally, and trying to optimize get to the most of it
i definitely do not recommend to try to fool google nor any other advertiser. i think we earn money in an honest way (;-)
you try and fool google and they will take your money and your account from you, you are lucky they only tell you to fix whatever you did.
g offers some "start and stop" tags for adsense, so you can say "this is the interreting part on my website, ignore the header, footer and my shoutbox for choosing ads", this is the save way. if you wanna cheat you can do it quite easy with iframes. make a plain page with your g-ads on top and add some text and title tag with you keyword. now insert this page with "your keywords" on your website using iframes, remove the borders and scroll bar from <iframe> and make it exactly the same size as your g-ads format, so your keywords on this framed page are invsible. dont forget to start a "im banned from adsense" thread a few weeks later