All these incentives are aiming at fostering the right eco-system. However, it might run into potential conflict of interest with advertisers. Plus, have you heard of Google Atom Bomb described below?

"Much blog buzz about Tom Foremski's doomsday scenario for Google AdWords. A billionnaire (presumably Bill Gates in disguise) offers $100-million dollars to the first person who clicks through an unidentified AdWords ad. I suppose the landing page would exist in isolation with no incoming links, and would contain a form to fill out. Millions of people would take up ad-clicking as their new hobby, tromping through legitimate landing pages and hoping to stumble upon the winner."

Microsoft Corp. launched a campaign last week offering $1 million in prizes -- including two free nights at the Four Seasons and a $500 American Express gift certificate -- to users of its MSN search engine. The random prizes are given to people who search for one of roughly a thousand terms on a rotating list. A new site called GoodSearch.com, launched late last year by Los Angeles-based GoodSearch LLC, aims to lure repeat users by donating roughly a cent to a charity of the user's choice every time a search is conducted on its Yahoo-based search engine. Amazon.com Inc. offers regular users of its A9 search engine a 1.57% discount on most Amazon.com purchases. Blingo.com, powered by Google, gives away prizes like iPods and movie tickets to lucky users who happen to search at random times.

Yahoo Inc. also might get into the loyalty game. Earlier this month, the No. 2 search engine surveyed some Yahoo mail users about the kinds of gifts -- from music downloads to airlines miles -- that would entice people to use Yahoo as their primary search engine.