Atchoo is a small application that connects with your Google Calendar, and provides you desktop alerts when some event is approaching.
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On initial startup, input your Google Calendar Username and Password.
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After that select the calendar for which you want alerts and then end the configuration setup.
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Now, it will sit in the system tray and when the time of an event is reached, a desktop notification will pop-up, allowing you to either snooze or dismiss the alert. Snoozing time can be entered in text (ex. 1 hour 5 minutes) or select from drop box.
Atchoo runs on all versions of Windows.
Download: Atchoo