If you want to monetize your RSS feed, but you’ve not been invited to the Feedburner Ad Network (you need a large user base or to be part of a monetized feednetwork) you can try Pheedo.

Pheedo offers feed advertising even to the micro publishers, with 3 different options:

• A feed hosting service (like feedburner) integrating ads and offering statistics and reports
• Platform-specific code to insert into your feed template (for MovableType, WordPress, TypePad Pro, Expression Engine, pMachine Pro, and Xaraya users)
• Simple html code to insert into your feed template

The first option is very simple to set up, and can be coupled with feedburner (i.e. you can have yor feedburner feed pointing to your pheedo feed pointing to your “original” feed…), the other two options are a bit tricky, because you have to edit the code of your blogging platform.

Advertising is category-based, so you have to choose the best category for your blog, and is both CPM (Cost per Mille) and CPC (Cost per Click) based.
Payments are sent 90 days after the end of the month you reach 50$ (that’s lame… waiting 90 days online it’s really too much)

I added pheedo advertising to my rss feed, I’ll let you know how it performs .

For other feed monetization options, you can have a look at this list of rss monetization strategies at DoshDosh.