Nice selection there Hamish, especially the more unusual items. I too have the 28mm Ultron and the 75mm Color-Heliar. I have the M-mount adapter rings but now tend to use them either on my Bessa R (LS) or using a mount adapter on a micro 4/3rds video camera as I have both focal lengths in Leica glass as well although the 28mm isn't as fast (but it's much more compact and a great travel lens). The 75mm is a lovely portrait lens though isn't it? As you know I've also got the Voigtlander 12mm f1:5.6 VM Super Wide Heliar plus VF but it's a tricky lens to use. I'll post a shot that was taken using it later. I bought the 35mm f1:1.2 VM Nokton when I bought my MP as it was faster than the Leica lens at the time but have since bought the new Leica 35 f1:1.4 which, although a fraction slower, performs much better on the M9 than the Voightänder - I've not made a comparison on the M6 or MP. I tend to keep just the 35 mm pancake lens on the Bessa R and it lives in the glove compartment of the car along with a couple of rolls of Delta 400.
I've also got a Leica 75mm f1:1.4, 50 f:1/1 90 f1:2.0 and 135 f1:2.8 (the one with the VF converter) along with a couple of ZM lenses. I'll try to get them all is the same country so I can do a 'group shot'.
The bodies are: Leica M6, MP, M8 and M9, Voightländer Bessa R and Zeiss Ikon.
I've also got a Mamiya 7II with a few lenses which used to be my travel camera of choice but I haven't used it for a couple of years. Must get it out again as it is a great system and capable of astonishing quality.