This applet is a viewer solid 4D hyper blocks (objects created by amalgamating hypercubes). The program uses a reasonable complicated algorithm to decide whether drawing certain lines are redundant. Do a bit of exploring with the colours and grab & rotating with xyZ and xyW. Also take a look at some of the different patterns.
There seems to be a bug in the program that appears with certain configuration none of which you can see. As well, I am sloppy with the number of points that I rotate. There could be up to 4 copies of one point in the points list. This could be easily fixed by some more programming but I'm lazy. If anyone is finding speed an issue I could probably double the speed. Take a look at the poorly documented program and its helpers O4matrix, Rotator, and HBlock.