I installed the latest beta of ObjectDock to see how it performs and did the following:
Shutdown the main dock (leaving only the tabbed dock)
removed taskbar and system tray tabs
removed all docklets
removed start menu
redirected a couple of shortcuts to my favoured apps (Take Command for the command prompt and PSP X for graphics)
Closed it and restarted it: RAM usage varies between 12 and 15 MB. This is a vast increase over 1.3, isn't it? With 1.3 installed, memory usage even with all the default settings was much less and configured as I have it above was in the 1.5 MB range. I realise that this is a beta, but wanted to note the larger footprint for development purposes....