I've been writing occassionally for PayPerPost. Its been a very good and extremely motivating experience. My revenues for this experience are increasing every month, almost every week.
If you'd like more information about PayPerPost and their Consumer Generated Advertising Program, feel free to drop me a comment or email. If you have a great blog that's more than 90 days old and has been maintained with regular posts, you can diversify your advertising revenue with PayPerPost. I can vouch for their regular and timely payments and the growing PPP community includes a great bunch of people. If you want to sign up just give them my email address brettbum at yahoo dot com. (Disclaimer: I get $5 for referrals, which isn't going to make me rich or anything.)