This was something I did five years ago, so I don't remember the improvements exactly, but in my situation I took an AdSense banner that was above the article title, and moved it here:
Originally Posted by Mike Dammann
Article Subtitle (teaser)
In this situation it tripled my click-thru.
The website has all original quality content and has been up since 1998. Unfortunately, despite the high volume of traffic, the target audience (electrical engineers) is marketing-adverse and doesn't t like to click on ads as often as, say, WWE fans. I suspect I can use my time more efficiently in other subjects and see a better return.
Failures Make Excuses, Leaders Find Solutions