Young Tulip -- NEX-5 & Kern-Bolex 50mm f1.3 Projection Lens. Click for larger.
I don't know why this pictures remembers me of the old Elvis song. Very strange.
These projection lenses are really good for low light, since they are very usable wide open, and they usually have a very large maximum aperture. I especially like the Kern-Bolex 50mm f1.3, even though it has lots of purple fringing. It's so insanely sharp and is much easier to hand hold in low light, due to its shorter focal length.
Still have three projection lenses I have not tried: Rodenstock Splendon 300mm (with no max. aperture marking), Leica 200mm (also has no max. aperture marking), and a Bell & Howell 76mm f1.6. I don't think I will be able to make the 300mm usable, as it's far too long and hard to use. The Leica and the B&H I may try, but I think my hand is full with three working ones at the moment.