AdBrite is a successful and popular advertising network and a good option for those that may want something other than Google Adsense.
They have recently advertised over 568 million impressions a day on 21,604 sites. Sites using AdBrite include Excite, Friendster, Linked In and more.
AdBrite has many different programs to explore and is a good option for both publishers as well as those looking for places to advertise.
You can allow advertisers to buy ads directly from your site, specify the minimum prices and even have other advertising take its place automatically if AdBrite payout isn't enough.