SAIL  Works like a dream on Panther.

Very useful for those like me who's mind (and fingers) wonder when they are supposed to be working instead of surfing! Works as a reminder to get back to work, but also as a way to split chucks of work into manageable sections of time, all completely configurable!

Great that you can set sounds for when your break comes and when it's up!

If nothing else, you should give this a try!   
(Version 1.4)