NetFPGA is a great development board with a lot of features. Unfortunately its size and research quality software/firmware do not make it a suitable device for deployment at scale into production environments.
I see they haven't done 25 GB / 100 GB stuff yet.
you can get a nice "SmartNIC" from Silicom that has a Tile Gx-72 and a Virtex FPGA on-board. I have no idea how much they cost; only that you can't buy just one :(