I was in Athens, now I'm temporarily in Berlin. I don't want to change the system time, it's perfectly correct. I just want the system to display the time in a different zone. I shouldn't need superuser rights to do this, I don't want to modify the default zone for the system, just for myself.
If this isn't possible through GNOME3's user interface, can I perhaps do it by editing a configuration file or something? A user configuration file that is, not system. .bashrc
wouldn't do it I believe, it would only affect bash.