Actually I'm in the early stages working on a K1 port for BitFury's chips (I'm calling it for the moment Project NanoFury). I'm planning on having the finished PCB have the exact same dimensions and heatsink holes as BKK's K1 (so that any plastic/lids/heatsink designs can be reused). It is going to be 1BF chip USB2.0 based solution so that it fits in the 500mA, which means that I may have to underclock the chip slightly. It should still do around 2GH/s though, possibly with the benefit of less heat.
I'm planning on replacing the PIC with another chip which will be $1-2 more expensive but will save me some time as I'll have less software to deal with (at least initially). I guess I should probably start my own separate thread so that we don't get off-topic here. I don't know if there will be any interest at all though.

And about that KiCAD .. what a pain! I've wasted more time trying to do simple things there than doing actual design and testing... and I thought switching from Protel/Altium to Eagle was painful...

And kudos to BKK again for all the great work!