looks like a new class of hardware component emerging - NIC with an additional FPGA chip. Or may be a NIC which has only FPGA, an FPGA larger than the NIC's code alone would require. Or just FPGA card with NIC ports on it.
http://exablaze.com/exanic-x10
http://exablaze.com/exanic-x40
We also build switches this way too:
http://www.silicom-usa.com/pr/server-adapters/programmable-f...