Trout's Internet Clock 

Desktop Clock, Scheduler and Time Synchronizer. Liven up your desktop with clocks of any shape, size, color. Schedule multimedia, text reminders, run programs. Synchronize your system clock. Dynamic system tray icon, semi-transparent clocks.
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TWAtomTime 

Time syncron with timserver ntp
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Time Sync Pro 

Time Sync Pro is an application that connects to one of the many atomic clock web servers, downloads the time to your PC and adjusts it. Time Sync Pro has many features including the automatic adjustment of your computer clock.
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Alarm Clock 

This program is a customizable alarm clock. It allows you to set a different alarm for each day of the week as well as disable the alarm for that day. The alarm sound can be set to any .wav sound of your choice. The display is large and easy to read
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Chronos Clock 

Desktop clock allowing multiple clocks & timezones. Timers, multi-function Alarm feature. Calendar/Memo Diary including reminder feature. Speaking Clock using MS Agent.
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Atomic Clock Service 

PC atomic clock synchronizer with some useful features (time offset, synchronize periods, etc.). This program uses the list of 19 presetting atomic time servers.
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