My local time is CET (Prague, EU), I also need to see UTC and, some times, MSK time. Can I add multiple clocks with different zones to a panel in XFCE? I know how to add multiple clocks, actually, but how to customize time zone of each of them?
It's possible to display multiple timezones by using multiple applets of the Orage Clock Panel.
Under Orage properties (right click on the clock -> properties) there is a button next to 'set timezone to:' labeled
Each applet will use the timezone you set it for.
by the way, I noticed you state you use Arch on your profile... Orage isn't installed with the base xfce package under Arch-Linux... it is part of the xfce4-goodies meta-package:
...almost, with its "Global Time" application which...
But I cannot find anything about this feature inside an applet...