It's of no real interet to me at the momnet (obivously) but this month's Elektor magazine (the summer double issue, so it's not cheap!) has a project to make a USB to GPIB interface. It's little more than a programemd PIC which directly drives the GPIB lines without buffers. I don't like that much, but... I think you can get source code for the firmware (apart from the USB routines, which are standard routins from Microchip). May be of interest to somebody here.... -tony