These guys have a functional meshnet setup. They also sell the hardware but it is not needed for their software.
Since the release of the original MeshAP boot CD, there has been huge progress with the project. They have a bootable CD which you can use in a laptop or regular PC with a wireless adapter and it becomes a mesh enabled thin client, wi-fi hotspot, bridge, repeater and gateway.
http://www.locustworld.com/
