Best Revenue Sharing Plugins?

I am looking for the best plugin to allow authors to enter their own ad code from any ad network they like… Maybe it doesn’t need to be a plugin?

Basically, I want to allow anyone with the “Author” abilities to enter the ad code from ANY ad network they wish on their profile page, then display it through a template tag 50% of the time. The other 50% it will display the ad code I have entered myself.

I am stumped, basically because everything I have been searching for and finding seem to deal with AdSense specifically and the publisher ID. I do not use adsense, so I would like a more generic alternative.

I don’t mind if it is a premium plugin or a code snippet to add to my functions.php file, either is fine with me.

Thanks for your time!