I needed a small shelf I could thumbtack to the wall so I drew this up in Tinkercad quickly. The first time around I made the walls 1/16" thick and it warped all up when printing, so the second time around I added in some more diagonal supports and made the walls 1/8" thick. This one takes a little more time to print, but turns out pretty decent. The version in the picture was printed with some Zentoolworks Clear on a Davinci 1.0. You may want to rotate this so the holes are down and also rotate it 45 degrees on your bed if you have an 8x8 bed so it will fit.