In XFree86 3.3.x, it was possible to allow the localhost to be able to use the X server so that you could allow the localhost access, change users and run as that user.
I remember a friend mentioning that XFree86 requires something be put in .Xauthority, but I wasn't sure what it was. Can some kind soul supply me with the setting in .Xauthority that will allow that? (possibly a Michel Dänzer question) -- Alan DuBoff Software Orchestration, Inc.