Various FPGA suppliers claim that their devices are increasingly used in mass-market consumer devices. Given the general depreciation of device prices with time, and high price for even old FPGA boards, this opens possibility to "scavenge" the boards for use as accelerators for various projects, via JTAG or other interfaces onboard.
For example, it's rumored that many 10Gbit ethernet switches and broadcast-level Video Processing appliances use FPGA's. In fact, some old extension boards from such devices can be bought from ebay for $50 a piece, which contain various FPGA devices, such as Xilinx Virtex-II, for example (make a search on ebay for "virtex", sort by lowest price).
Such techniques were used by CCC in 27C3 conference, for example, to brute-force DSA key recovery, using recovered FPGA boards from video processing equipment, bought on ebay.
A more recent example, new Apple MacBook Pro's include an FPGA (search for "Macbook FPGA"). Many Network IP Cameras contain FPGA's too (often Xilinx Spartan-3 variety). These cameras cost quite a lot new, but sold for next to nothing when replaced by new ones.
A list of devices with their FPGA variants would be a great help to both people starting to learn about FPGA's and people that want to test new ideas with larger or multiple FPGAs.
A valid answer would be a new list (preferably wiki-editable) or pointer to an existing list of devices that can be found on the market for relatively cheap and have relatively modern FPGA chips inside. Relatively modern in the meaning that the modern design tools by either the FPGA manufacturer (Xilinx/Altera/etc) or non-hardware company (Aldec, Mentor Graphics etc) support the recovered FPGA as target, either natively or using some simple workaround method.