I have an extra (maybe 2 if I can find it) 3.8MM gamebit. You can use it by hand (that's what I do) or use it as a bit for a screwdriver or drill.
It works like a charm on NES and SNES games, but isn't the right fit for GEN.
If anyone is interested, let me know (what the hell am I going to do with 2 or 3 of these things?)
Steve