I want to start this off with a couple of warnings:
- This is not something for the total noob. I don't think you'll hose your machine, but you could very easily end up burning a lot of space not only on the /media/internal area (the USB disk space area), but also in the /var partition, which is limited enough as it is (which is the root of the problem). I'd say this is for an intermediate level user, and it does require root access.
- I'll also warn that I have not tested every aspect of the script. Use all of this information at your own risk, and please double check stuff, as it does very much appear to be a "work in progress".
All that said, here's the basics:
This workaround has you create a hidden directory - .apps - (please note the "." before "apps", that's what makes it hidden) in the /media/internal directory on your Pre. This is basically the USB drive, and has a lot more space than the /var partition (where apps are normally stored). You then copy some apps to that directory, and create a symbolic link to the new directory. Every program I've tested this with works, so far. This has cleared up a lot of additional space for me.
Please look over the information provided in a the link, move slowly, and double-check what you've done; however, I think some of you will find this useful until Palm does something about the size of the /var partition.
Solution to App Catalog Installation Limit - WebOS Internals