by Proton, published
The ugliest shoe I've ever seen.
Probably does not fit anybody.
Horrible color scheme too.
But it has only 4 surfaces and renders in OpenSCAD!
Once the invalid polyhedrons (visible as magenta triangles) are sorted out, you can print it in leather or glass...
Slightly parametric too.
Put heels.scad in the same directory as http://www.thingiverse.com/thing:8907 and press F5.
CGAL rendering (and thus STL export) doesn't work (yet).
Once that is sorted out, print one and the mirrored version.