Looks even better with the ACE Foxdie theme Rated 5 out of 5 stars

Plus, I like the new foxkeh "mascot" image (he/she has a very "remember this or else" expression :D). I started using ReminderFox several years ago, but I've only used it off & on--some problems with custom sound files for alarms (and, to be honest, somewhat lacking in visual appeal--but Foxdie fixes that [even if it introduces some visual anomalies]). It feels a lot more "solid" now, with even more features. Thanks.
@Espyo (2010-12-15): did you check off the box for "Show alarm popup" when creating the reminder?

This review is for a previous version of the add-on (1.9.9.1).