BidVertiser Place the BidVertiser text ads on your website and make money online by getting paid for every click.
 
 

AdBrite
 AdBrite, is currently one of the best alternatives there is to Google's adsense. While they do not offer the same large selection of ad formats that Clicksor and Google Adsense provide you they do offer the most commonly used ones. In addition they offer inline page links with have some great click through ratios as well as interstitial full page ads which offer an excellent way to monetize all traffic to your site not just traffic that clicks on your ads. Their payouts are also very competitive. They have more relaxed terms and conditions than Adsense and are much more accepting of smaller publishers including bloggers.
If you're a publisher, use AdBrite to set your own ad rates, and approve or reject every ad that's purchased for your site or just have AdBrite auto accept ever ad. AdBrite enables you to instantly sell ads to your visitors via a "Your Ad Here" link, in addition to selling through AdBrite's marketplace and sales team.

 
Clicksor
 Clicksor is one of the current leaders of the small publisher Adsense competition. They have payouts upto a market leading 85% and unlike a number of alternatives the cost per click bid values are high enough that you can earn a decent income. They are also, in my experience, much more tollerant than Google. Their terms and conditions suggest that you should only place one copy of their code on a page but as long as you only place a single pop-up or DHTML code on a page they seem happy to let you place many context sensitive ad blocks on a single site.
 
 
 
Yahoo YPN
 
The best adsense alternative, but is open only for US publishers.

 
 
 
FastClick.com
 At first look FastClick would appear to be one of the better alternatives to Google's Adsense however, they are one of many online advertising companies that tend to favor the large customers. You'd think companies would have learnt from Google's success and accepted that the way to make money is to target both large and small. Remember Excite? They went the way of the dodo because they only targeted the top 100 companies rather than the small guys who can't afford large TV adverts and have to advertise on the Internet instead. Anyway, I digress. If you can get yourself accepted to FastClick (now called ValueClick) then you will probably be able to run some reasonably high paying adverts on your site but most small website owners will find that FastClick simply aren't interested.
 
 
Tribal Fusion
 
One of the top eCPM advertising network with good payouts. However, only sites with a minimum of 2000 unique hits per day can apply. Rating 4.5/5

 
 
 
RevenuePilot.com
Revenue Pilot is a great alternative to Google's Adsense. They provide a large number of different ad formats and also provide access to a unique "CHECK PRICES" tool which allows you to enter a keyword and see how many advertisers are currently offering ads on this keyword, how much they are bidding and how much Revenue Pilot will pay you. This is an awesome tool that gives you as a publisher the opportunity to carefully optimize your site for maximum payout or as an advertiser to research neglected keywords, see how much others are bidding and so make your advertising budget go as far as possible. As far as I am aware no other Ad provider offers such a useful tool.