This is an entry for the birdhouse competition. It's a nature-inspired design that should allow ventilation, keep light and water out, and be very structurally sound (caternary arches) while using little material.
I used MakerWare and my Replicator 2X. I printed in ABS at 240 degrees F and heated the build plate 120 degrees F. I have only so far printed a small scale model and used the makerbot slicer at .34mm thick layers, 5% infill, and 3 shells. The uploaded STL is upside down, however.
The STL I used was really fine quality. The model uploaded to the Thingiverse is of lower quality; I was having trouble uploading the larger file size. I don't believe this will affect the print quality drastically, but have not tested.