Hi there,
I have an x6500 miner that served me well until around a year ago (probably long after it was profitable to mine with it), that I am now looking to sell. I have not used it in the last year, so don't know if it works, but I imagine it does. I am not sure if they are still useful for mining (altcoins), but I know the FPGA's themselves are worth something! I'm not sure if it is very much, but I seriously doubt that I am going to use it again.
I believe these have two spartan-6's in them, if you are more interested in the chips themselves. More at
http://fpgamining.com/Paypal or bitcoin is fine with me. Make me an offer! I will review them all tomorrow! I am only willing to ship inside the USA, unfortunately.
Thanks,
SirKy