JOTSA is a animation package under development by Steven Robbins at the University of Texas at San Antonio.
JOTSA stands for Java On Time Synchronous Animation.
JOTSA development is supported by two NSF grants.
There are several papers and technical reports about JOTSA and about applications which use JOTSA.
Here are some example animations built on JOTSA version 0.924:
The following are available for downloading. All are gzipped tar files (Unix).