BSPP = British Standard Pipe Parallel and is coded as a "G" thread in Germany
It's a straight thread with a count of 19. Very common for watercooling equipment now because it allows you to use an O-Ring instead of teflon tape.
Most manufacturers use it now, except swiftech (they use NPSM).
I've only found a BSPP tapping bit through
http://www.Mcmaster.com but it might be available through other sources.