Move Windows profile directory?
copy profiles to u:
change
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList\ProfilesDirectory
value for future profiles and corresponding ProfileImagePath values for each of your existing (and relocated) profiles.
or just add this to startup:
subst u: "C:\Documents and Settings" :)
links approach is good too. http://schinagl.priv.at/nt/hardlinkshellext/hardlinkshellext.html this tool seems best in convenience to operate with them.