I built an ICD2 clone, from the PiCS design rev B from icd2clone.com, which is based on the information in the forum thread that started it all on EDAboard.

I suffered the misfortune of almost completely constructing my first one before realizing that acrobat reader had scaled the pattern when printing it, so the whole board was at about 90% scale and was thus useless.  Getting the board working with MPLAB also proved to be a challenge, involving uninstalling/reinstalling drivers a few times, burning the bootloader firmwares into the PICs several times, etc.  I ended up adding a couple of 0.1uF capacitors directly across the Vdd and gnd lines under each PIC (I used 0805 SMD caps, they fit perfectly) and it was soon after adding them that I finally got the board working in MPLAB, so I suspect that their addition made a difference.