A MUST! Rated 5 out of 5 stars

Great interface usability and incredibly complete: let's you subscribe to .ics (Google calendar), alerts have a snooze button, link to URL or file, context menu..
A must for anybody like me that tend to lose track of time browsing.
Thank you, thank you so much!
====UPDATE===
Now that I've been using it for a while I wonder if it would be possible to add an option - I think should be added to all reminder apps - that says: ' If the alert is not executed after X time (eg. because the computer was off) cancel it'
It would avoid getting tones of alerts popping up after, for example, going away on vacation.

This review is for a previous version of the add-on (1.9.1).