Used SymmTime for Windows?
Editors’ Review
Unlike similar applications, SymmTime works like clockwork when it comes to keeping track of any of the 24 time zones around the world. It synchronizes your computer's system clock to one of several free external timeservers, so you know it's never off. The basics are well-covered here, too, with all changes accessible through the context menu.
Setting the multiple time zones to multiple clocks, choosing colors for the analog faces or fonts for the digital ones, renaming zones to represent your favorite locales and even setting the clock panel to a favored place on your desktop are all straightforward and intuitive tasks. This program has neither bells nor whistles--no time zone maps, no sunrise or sunset information, not even an alarm clock. However, for a freeware, customizable, multi-zone world clock, you'd think SymmTime was Swiss-made.
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