[X4U] Any way to hide a user account?

[B. Kuestner]

The UID has to be <500 and the home directory should not be located  
in /Users.

For example the root user meets both criteria. So it is permanently  
accessible (once enabled; not recommended) but not visible in the  
login window or in /Users.

But there is no "simple" way to achieve that. You should be familiar  
with Unix internals, the Terminal and/or Netinfo.

Björn