Light in the Box offers this GM60 Mini LCD Projector in White for $41.59 plus $11.54 for shipping during its ongoing clearance sale. (Black ships for a few bucks more.) That's the lowest price we could find by $17. It features a maximum display resolution of 480x320, support for a screen size of 34" to 130", USB, and HDMI and VGA inputs.

Note: It supports 1080p resolutions, but it's only capable of outputting 480x320. Uncheck "Add Shipping Insurance to your order" during checkout to remove the 99-cent fee.