Best Buy is now selling the 8GB model of Apple’s iPhone 4 for just $49.99 with a new two-year contract on AT&T, Verizon or Sprint. The phone’s typical retail price was $100 with a new two-year contract from a carrier. It’s unclear what caused the price drop, but we’d guess Best Buy is starting to empty its inventory in preparation of the iPhone 5 — or whatever you choose to call Apple’s next-generation iPhone. There are a few sacrifices with the iPhone 4 over the iPhone 4S: the phone has a slower processor, less storage and doesn’t support Siri functionality. If you’ve been holding out for an iPhone at a more affordable price, however, the iPhone 4 could be right up your alley.