Over my holiday vacation I ran into some weird crashes while in Gnome on my Debian Etch box. Since I don’t know enough about the internals of Gnome to do any serious debugging, I took the cowards way out and deleted nearly every dot-file and dot-folder (where settings are kept) in my home directory.
I kept e-mail, favorites, and the like, but everything else went. I was shocked to find that not only did it fix the crashes I was experiencing, but Gnome seems to run at least twice as fast as before.
It only took me about 10 minutes to reset all of the preferences I care about, so my advice to anyone who’s beeing using Gnome for a while and experiencing crashes, unresponsiveness, or slowdowns: nuke 90% of the files and folders in your home directory that begin with a dot.
Warning: Be smart, and back everything up first!