Petri CC Auto 55mm f1.8
This lens is not the prettiest or best built lens but it performs well. It is sharp at f1.8, but that's not what makes it special.
Images from this lens have a nice 3D feel to them. Bokeh is very natural at wide apertures. Micro contrast is excellent. It reminds me of a Konica Hexar. I am confident this will be a great portrait lens. Color rendition is accurate. Saturation is neutral and contrast is excellent at all apertures.
At $25-$45 this lens is a tremendous value.
I tested the m42 version of this lens and it handled very well on my T2i. Finding focus was not an issue and the aperture ring doesn't bind on the adapter.