If you want something exotic and faster than the canon 50mm 1.2, then look on ebay and find the canon 50mm 1.0L....
Yep, that's the answer if owning a 50 faster than f1.2 on a Canon DSLR is your quest.
Unless of course you want a very fast 50 macro lens - then the Leica lens on your Canon would be good. The Leica M mount has a flange distance of 27.80mm, and Canon EF is 44.00mm. If someone was to make an optics free mount adapter that was just 1.8mm thick, that and the difference in flange distance would be the equivalent of using an 18mm extension tube. Infinity focus would be far from possible, with the minimum magnification probably somewhere around 0.40x.
If you're determined to use the Leica 50/0.95 on a FF camera other than a Leica, I think you're only option is the Sony NEX-VG900
and an M to E mount adapter
. I'd much rather one of the Canon 50L lenses on an EOS body, or a Leica body to mount the Leica lens on.