Microsoft MN-500

See also the Microsoft MN-100 on the Hardware Recycling Initiative website. Per their site, the CPU appears to be ADM5106 compatible.

Internal shot on the DD-WRT forums

The power adapter included with the device is a Foxlink FA-4A030-1 (12VDC, 500mA). It has a barrel connector with a reversed gender core (that is, it has a pin).