Datetime 

Active Calendar is an ASP.NET server control that allows users to select a date and/or time quickly using a professional looking date picker with a client-side managed event system. No postback to the server required, no external script file required......

XDeskCal is a pretty,fully customizable calendar features Todo-list,Appointments,Alarms,Holidays and displays its data on your desktop. It is a very lightweight application that doesn't use much system resources or take much space on your desktop.
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XDeskCal is a pretty,fully customizable calendar features Todo-list,Appointments,Alarms,Holidays and displays its data on your desktop. It is a very lightweight application that doesn't use much system resources or take much space on your desktop.
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Chronos is a time logging program for AutoCAD.

Chronos will log all users that access AutoCAD drawing files and provides comprehensive reporting tools for documenting AutoCAD usage.

The drawing data that is logged includes:
Creation Date
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DateTime Calculator will let you easily add/subtract dates and time intervals, or compare two different dates/times. With just one click, you can add a value to a base date time, or subtract some intervals from a base date time, and get a detailed re......

 Datetime