Same problem with my 16gb A500 running ICS. I've had to restore to factory once already. Another forum listed the problem as a GPS file leak problem, better described as:
"The bottom line is that when the GPS is used, the GPS driver for ICS 4.0.3 on the Acer a-series tablets apparently writes numerous gl-YYYY-MM-DD-HHMMSS.txt files into the /data/gps directory. The files are apparently not automatically deleted, and so over time will consume most of the internal storage space."
If this is in fact the problem when can we expect a patch to fix this seemly simple issue?
What is the status of the patch necessary to fix the GPS memory drain and remove the excess files to restore the available free memory? I am on the edge of the painful process of a factory reset, but can hold off if a patch is to be released soon...