you think side window is useful you should try Desktop Rover from Neslo software.
This allows you to use your PC's mouse and keyboard on your PPC while its connected via activesync.
you just move the mouse over onto the screen, and start using the PPC like the keyboard and mouse is plugged into it.
you can even paste text back and forth between the 2
I use it to control 3 PC's and a PPS all from one mouse and keyboard.
http://www.neslosoftware.com/