From Semantic Engines:
LinkSensor semantically analyzes blog posts or articles on-the-fly and highlights key concepts in the text. When the user's mouse is over a highlighted word, a small balloon shows up suggesting other articles from the blog related to the word, or a relevant ad. Highlighted words represent key concepts of the article, therefore the user is likely to see a value in viewing their contextual links.
Key terms which we extract from the page allow the advertiser to select an ad which is relevant to the content of the page. Contextually-relevant ad is likely to attract the user attention, maximizing the advertiser's revenue. We have a real-time API to send you the extracted words from a page so that you select a matching ad on your end. We can also implement the ad-matching on our end. Contact us through LinkSensor website.
By navigating to other relevant posts, the user will discover more pages and spend more time on your site. This may directly result in higher ad revenue, or make your blog eligible to get bigger advertisers. If you have more than one blog or site, you can redirect the users from one to another, all within the context of your post/