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CloseReview for ReminderFox by zer0rez
Rated 5 out of 5 stars
This light yet extremely robust calendar/reminder addon is deceptively powerful and is especially helpful if you work at your computer. Integrates nicely with thunderbird as well.
There is a brief video overview of it here:
http://www.youtube.com/watch?v=as9XUOFccGA
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