PlayStation 1 development kit - DTL-H2700 Performance analyser.
This is an ISA card that sits inside a PC, with a PS1 drive that sits in a 5 1/4 inch drive bay. It has a couple of advantages over the standard Devkits, most notably you can capture low level performance details such as chache hits, stalls on both the CPU and the EE. Original price for this bit of kit was I believe around £17,000, hence there aren't too many around.
Included in this sale will be the board, CD-Rom drive, Tools and Libraries CD and possibly, a contoller breakout box.
As it may be difficult to list on Ebay, I'll put it up as a one day listing some time next week. If you wish to take part in the auction PM me and I'll give you details of when it goes up.
There may also be a DTL-H2500 PCI DevKit available at some time.
Until then I'd consider offers over £750.