Canon FD 70-210mm f4 adapted to an Olympus E-M5 at the time, and I also added a Kodachrome 200 film sim haldCLUT to it in RawTherapee.
Assuming such a ring exists, I could probably attach an M42-FD adapter ring to my current lens adapter (which is now being used with a Panasonic GF2 as the camera that snapped this pic has since died of a stuck shutter) and use M42 glass without having to get a new adapter, which the adapter used in this shot is a Fotasy FD-M4/3.
If I’m remembering this right it was maybe two, I didn’t count.