Groupon—the online coupon, voucher, deal-of-the-day company—turned down a $6 billion offer from Google. For a business model that has very low barriers to entry (no fortress or moat as Buffett would say) and questionable value in good economic times, it appears they may regret turning down Google's big fat offer. That's not to say they won't get out making a killing, but it'll have to come by unloading their dubious business model onto the public when they go public. The dot com bubble redux seems to be alive and well with a $15 billion valuation of Groupon (still losing money!) and a maybe a $100 billion valuation for Facebook. It's absurd, but I guess the whole dot-com thing has been forgotten so Wall Street can begin the fleecing again—package it, hype it, sell it and forget it!
See here for more info on its business model and here for a sense of funky accounting since the real accounting would hurt that sky high valuation.