Happy fifth birthday, Bing. The engine is celebrating the big day by giving those who sign up for the Bing Rewards program up to five times the credits when searching on Bing. Each day that members sign in and search from June 3-9, they will earn entry into a contest for the Bing Rewards prize pack. Five winners will get an Xbox One, Surface Pro 3, Nokia Lumia Icon, $500 to spend on apps and entertainment for Xbox, Windows 8.1 and Windows Phone 8, and more. Searching on Bing enables consumers to earn credits redeemable for popular gift cards, services or donations. In fact, each month Bing searches could earn enough credits for a $5 gift card to a retailer including Amazon.com, Fandango, Dominos, Sephora, Xbox, Toys R Us, or a one-month subscription to Hulu Plus or Skype, and others.