Just a little hollow sine vase.

I made this in Openscad and printed it on my Printrbot Simple Metal. I printed this without supports, 20% infill, with IIRC 4 side walls, and added a 2 mm brim to make sure that it didn't come detached. Oh, this is also scaled up by a factor of 1.5 and at that rate ends up being about 3" tall.