CowBoom offers the used Microsoft Xbox 360 E 250GB Console, model no. M9V-00001, for $69.99 with free shipping. That's $35 below our winter mention and the lowest total price we've seen. (It's also $210 below the best price we could find for a new unit.) It features 250GB internal memory, WiFi, and a wireless controller.
Note: No warranty information is provided. This used unit may be missing parts or accessories and have dents or scratches.