Yashica Electro 35. David Mingay has one too. Only one other pbaser has one featured in his gallery.
Playing with my SB-800 in manual mode, main light was above at 1/64 power and 45 degree tilt with white card pulled out, and a flash head width in front of the subject. Flash on camera was at 1/128 power and pointed straight up to trigger the main light. Coolest thing is how sharp this lens is.