It appears that the more items you have on your desktop, the more RAM is in
use by Explorer.exe (in Task Manager - the first instance of Explorer.exe is
your desktop shell). It doesn't seem to matter what size the actual file
is, it just allocates memory for the icon to appear on the desktop, so it's
just a few K. I tried copying a Word document (116K) multiple times on the
desktop and it only increased memory usage a little bit, nowhere near the
size of the file - and no, they weren't shortcuts. I'd say it's a minimal
usage of RAM, but better organization not to clutter the desktop with actual
files. Shortcuts are much smaller, and users could actually have a shortcut
to a folder full of files they use.