Thanks,
The simplest thing is to use a networked filesystem -- NFS, SMB, etc.
This is probably the solution I will go with but how can I link to files on a NFS. Would you alter it so all wiki files are automatically saved to this location instead of wiki/images (If so do you know what settings to change?). The other option would just be to have users save files to the NFS then create links to those files in the wiki. I'm not sure but at the moment the wiki seems to only accept valid html links (I don't know how to make a link to a Network Shared file)
Any help would be greatly appreciated.
Thanks.