SyncBack may be an alternate solution to look into as you have XP Home, although it would not be ideal by any means.
You would set up a two-way sync between a local folder on your computer (e.g. c:\local_cache) and the network share in question. You could then set up changes to replicate backwards and forwards every 5 minutes or so, depending on the number of files on the network share.
Giving the local folder a drive letter is easy enough using the SUBST command from the command line. subst z: c:\local_cache
for example.
If you are looking at a solution that offers realtime synchronizing (or caching), I think that would be a bit more tricky and would most likely involve software having to be installed on the actual computer hosting the shares. Take a look here on lifehacker for a bunch of suggestions. Not really an option if the network shares are hosted on a corporate server, but hey, there is always SyncBack.
+1 This works well in most cases. If the amount of files is large, the first sync can take a while, especially if you have a slow connection. You also need to be aware that you will be prompted if you try to sync a file and a newer copy is on the server. If you are mainly reading, this should not happen much. Just be sure to read any warning popups carefully. Just make the ones you use most available offline. You also need to know that this must be enabled on the server. – Dave M – 2010-02-09T20:38:16.610
Unfortunately I have XP Home. Thanks for the response though. Will update my question. – danio – 2010-02-09T20:38:38.513