Unsteady (time varying) computational fluid dynamics. 200+ GB. 90,000 time steps with 20 MB files and numerous aux. files. Flow around a descending VTOL aircraft.
The largest dataset I have heard thus cited at LLNL was the California State water resources data set 100 TB which is being worked on by the Sequoia 2000 Project (UCB, UCSB, DEC, and others). Military and intelligence datasets may be larger.
--eugene miya, NASA Ames Research Center, eugene@orville.nas.nasa.gov