TechBuffalo has posted a photo of what appears to be a genuine ad, announcing that the iPhone 3GS will be free with a two year contract at Best Buy Mobile stores on Monday, August 22.
This is the second time Best Buy has offered the iPhone 3GS for free with a two-year contract. The first was back on December 10, 2010. However, while the December sale was good in all Best Buy stores, the flyer for the August 22nd sale only shows the Best Buy Mobile logo, so we'll have to wait and see if the sale extends to the regular stores as well.
If you want an iPhone, this is a great deal. The iPhone 3GS runs iOS 4 just fine. However it will run iOS 5 without some of its marquee features. For example, the iPhone 3GS will not have the ability to edit images using the red eye removal, crop, and enhance tools in the iOS 5 Photos app.
Also keep in mind that the iPhone 3GS will probably not be upgradable after iOS 5. If that stuff doesn't matter to you and you just want a free iPhone, head to Best Buy Mobile stores on August 22nd!