zerOnet offers a small modification for DOOM 3 engine games that can significantly reduce the network usage in DOOM 3 (and the expansion), QUAKE 4, and Prey by an average of 50%. Word is: "The new snapshot sizes range from 10% to 90% of their original size without changing any of the original code's reading/writing data, all the bit sizes are the same and no functions have been swapped with smaller versions (eg 'WriteShort' instead of 'WriteLong')."