The Quad V7 TAI Logic Module can hold designs up to 80M ASIC gates with four Xilinx Vitex-7 2000T FPGA devices and has two on-board DDR3 SO-DIMM sockets and two on-board DDR2 SO-DIMM sockets to meet a variety of high-speed memory applications. The Quad V7 TAI Logic Module supports 48 channels of high speed Gigabit transceivers capable of running up to 10Gbps for a variety of high-speed interfaces such as PCIe, SATA and XAUI. In addition to our existing USB2.0 port for our popular runtime software features such as FPGA download, programmable clock generation and self-test, the new Quad V7 TAI Logic Module now supports these runtime features through Ethernet cable so you can control your FPGA hardware remotely. S2C has also added a number of new runtime features such as I/O voltage setting and clock frequency read back through software control.
http://www.s2cinc.com/product/HardWare/V7TAILogicModule.htmhttp://www.s2cinc.com/product/HardWare/images/quad_fontcheck.gifOf course I couldnt find any prices on them but would guess a few thousand or even more, the unique thing is that they can easly be stacked.