A number of new search engines have resorted to paying users to run searches on their engines. Ross Dunn at WebProNews writes:

"If at first you do not succeed, try and buy your market share." Okay, admittedly this is a bad example of the mantra I am trying to get across but it does fairly represent the enticements a couple of search engines are using to attract users; Blingo and AGLOCO.
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Each of these search properties are built on the basis of making money off you, their advertiser. In fact, that is their entire business model - attract the users and the advertisers will have no choice but to come and pay well for visibility. My concern is that users who sign up to get paid to search may not be the target market for the average advertiser. After all, logically some of these users are on the search engine just to make an easy buck and are not necessarily interested in serious searching.

Indeed, the idea of paying users to search does represents a gross conflict of interest between advertisers and their adservers. If you find yourself having to work with such a search engine, however, Dunn offers some additional details and advice in the Complet e Article.