I also made some soft lenses for 35mm myself, you can check this article:

Monocle Lens

Russian photographers call them "monocle" since lense has the only element.
I like soft effect, though shooting monocle is not easy compared to regular corrected sharp glass. Adjusting focus and aperture can be tricky and it is suffering from purple fringing,strong enough to ruin you color pictures (BW with some filters is ok).
For the monocle you need simple SLR with bright viewfinder, and old manual minoltas are perfect match. On the photo you can see my last creation -- bellows-based monocle "Big Bertha". See some example shots below and in my article above. If you interested, here is some photos of famous Russian artist (and monocle handyman) Georgy Kolosov:

Georgy Kolosov, "Religious procession on the river Velykaya",1993-1999