Carl Bialik from WSJ writes "Search engines are dangling rewards and cash prizes to attract customers to their sites, the Wall Street Journal reports. MSN is offering free nights at the Four Seasons and other goodies to people who search for one of roughly a thousand terms on a rotating list. Yahoo's GoodSearch donates a penny to charity for each search. And Blingo hawks giveaways including iPods. But, the WSJ reports, 'There are strings attached to some of the reward programs. Some require users to register personal information like a name or email.'"