One of today's Amazon Gold Box deals is on the second generation Motorola Moto G, arguably the best budget device on the market. For December 9th only and as long as supplies last, the price on the Moto G US and International versions in both black and white is reduced $30, down to $149.99.
If I had to buy an off-contract phone right now, it would probably be this one. Do keep in mind, though, that this kind of price comes with a few limitations. There is not yet a current-generation model that supports LTE, so if you want that, you will have to buy last year's LTE model. Also, Motorola does not make a CDMA version of the Moto G, so this will not work out for Sprint and Verizon customers. You do still get Motorola's very clean version of Android and speedy updates; in fact, this Moto G has already been updated to 5.0 Lollipop.
You can get a Motorola phone with a 5", 720p screen that has been running Lollipop since mid-November for $149 today. It might not be the best phone for everyone, but the Moto G is definitely among the better buying options for many.