A relative newcomer to the scene Infolinks specializes in In-Text Advertizing. That is it indexes your page looking for keywords and phrases that are not currently links and converts them into advertizing links. When a user places their mouse over the link a box opens up showing the ad. If they click on the link you get paid. It is very simple and works very effectively. The nice part is that you can use Infolinks to compliment an existing advertizing campaign on your website. For example you can show banner ads with AdBrite or Bidvertiser and show text links with Infolinks. Or you can even show text links with both AdBrite and Infolinks together on the same page to maximize your revenue.
Infolinks claims to be leading the industry with the most relevant in-text advertising links and the highest revenue share - guaranteed. I am not sure how they 'guarantee' this but having used them for several months I can attest that their payouts are indeed good compared to other In-Text advertizing options.
In-Text advertizing is also useful if you have a site under construction. For example, suppose you have built a list of links but have not added all the links yet. Infolinks will parse your page and convert a lot of these into links. People then think these are part of your site, click on them and you get paid. The unobtrusiveness makes it a very attractive way to monetize your site without inundating and alienating your visitors with flashing banners, pop-ups etc.
Infolinks pays you either by check or fee free by PayPal.
Quick and easy setup with no changes to your website
Ads are tightly integrated with your content - no additional space required
Free sign up with no commitments or risk
User triggered, less intrusive advertising that won't distract from your site's content
Highly relevant In-Text ads for your site visitors with record high conversion rates