Darwin, any chance you're running PS Tray Factory? I don't have anything concrete but I always felt it degraded my system performance. Just checked explorer.exe in Process Viewer and it's using 20,744 K (private bytes) - all my usual apps are running and I have over 20 icons in my system tray. Two explorer.exe instances is something I've never encountered noticed, BTW. Wonder if it has anything to do with a 3rd party file manager integrating itself into the system...