I probably should have posted this last year...
Last year around the release of 1.6 (or was it 1.7?) I discovered a bug in the LSL compiler; not really a bug so much as a bit of left over debugging code.
At the time I reported it and they removed the old debugging code.
The debugging code was for the collision_start event. So if you have a script that was last compiled before April 2005, and uses collision_start; you may find that recompiling the script will free up some memory (about 15 bytes).