SP TimeSync 

SP TimeSync is a multilingual program which lets you synchronize your computer's clock with any Internet atomic clock (time server). It uses a high precision network time protocol (NTP) which provides accuracy of several milliseconds.
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#1 Atomic Clock 

Atomic Clock synchronizing application with some useful options (skinned, synchronize periods, work as Time Server, import time servers list, etc)
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Trouts Talking Internet Clock 

Analog Desktop Clock, Scheduler, Time Synchronizer and Time Zone Viewer. Desktop clocks with any graphic. Schedule multimedia, text reminders, run programs. Text-to-Speech support with Microsoft Agent characters. Synchronize time with atomic clocks.
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