I designed this Thing for a science fair project (that incorporated solar energy) as a sort of picture frame to make it look like a sun was peeking out from the corner of the headings. I used 3 different sizes of the sun, and used it multiple times. (I got an "A".)
This file scales very well. I printed mine on a Bukobot 8 Vanilla v2 (a RepRap printer) with 25% fill and a layer height of 0.3.
I used Repetier as a host program on my printer, and I sliced the files into GCode with Slic3r.