What is the best placement of ads in a blog?

[ablaye]

For those who are making tons of money with PPC ads, what is the best placement of ads within a blog? By that, I mean which ad placement will get the most clicks and won't turn away your visitors.
Do you place ads within your blog articles, or on the header, footer or side of the blog?

[Jeremy]

I have a bit of success with keeping ads in two places. One, along side the content. In my case, just to the right of the content since I don't have a left sidebar (although many people will say the top left above the fold is gold). I have two ad blocks, one above the fold and one down slightly that aligns with a lot of the content. Clicks are consistent between the two.

I also use a piece of code that detects when someone is being referred via google search, and if that is true, a large rectangle is inserted into the content body. This unit has the highest CTR and eCPM, but since it only shows for search referrals the total dollar amount earned is still lower than the ads that display on every page.

[adalante]

So far for me the 336x280 size works the best in between content.