This should work for Windows XP. Of course, the main machine will have to
be accessable whenever you want to use IE on the secondary machine. Make
backup copies of your favorites folders befaore trying it, just in case
something goes wrong.
On the secondary machine, create a mapping to the drive on the primary
machine that contains the Favorites folder. You'll probably want to make
that mapping persistent. With IE closed, drag the Favorites folder from
the secondary machine to the parent of the Favorites folder on the primary
machine (most likely \Documents and Settings\{userid}), holding down the
shift key as you do so in order to move rather than copy the folder.
The idea is that you're moving a folder named Favorites to a location
where a folder by that name already exists. Windows will point that out
and ask if you want to merge the contents of the folders. Reply "yes",
the two folders are merged, and you're done. Since Favorites is a special
system folder, Windows watches what happens to it and when you move it,
the appropriate entries get updated in the registry. When you open IE on
the secondary machine, automatically see the Favorites folder on the
primary machine.
During the merge, any Favorite from the secondary machine will overlay a
Favorite with the same name on the promary machine. I you don't want this
to happen, delete or rename entried before moving the folder. If you
don't want to keep any of the Favorites entries from the secondary
machine, you can empty the folder before moving it.