This is a high quality custom cable made from forum user Cablez.

It powers six X6500 FPGA modules (barrel connectors) from a single PCI-E connector.

It looks something like this: https://bitcointalk.org/index.php?topic=74397.0

I can provide a picture once I disassemble my stack of FPGAs.

I'm selling this for 3 BTC and this includes USPS Priority Shipping.