There is an other FPGA Board at https://bitcointalk.org/index.php?topic=49180.

The Board currently achieves 190 MH/s on a single Spartan 6 XC6SLX150-3. For amounts of 5 or larger it is cheaper (i.e. more MH/s per $, see https://bitcointalk.org for volume discounts) and it is about 50% more efficient.

The Software is Open Source, see http://www.ztex.de/btcminer an reached a mature level. A cluster mode with hot-plugging allows to run many FPGA board from a single software instance.

Boards are available immediately.