Here's another variation (the last?) on the ball in cage design. I used Groboto for the basic model, distorted it in Sculptris and then added the ball in Cheetah3D.
The first time I printed this, I had the "puddle" horizontal but the grain in the cage looked odd since it printed it at an angle. For this version, I printed it with the cage vertical and the puddle at an angle. The grain came out fine then.
I used ReplicatorG on a MakerBot Replicator2 with the Replicator 2 slicing defaults and the following settings with white PLA from ProtoParadigm:
Infill = 10%
Layer Height = 0.200
Shells = 1
Feedrate = 40
Travel Feed = 55
Temperature = 220
I used a raft with full support.