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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PresenTense NTP Auditor 

PresenTense NTP Auditor monitors your computer's built-in clock and compares it's time to the real time. PresenTense NTP Auditor can save logs for days, months and years so you can PROVE what time your computer had at any given point.
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