I cant recommend this enough!

As a student, studying computer science, I spend many hours each day sitting in front of my computer. As a result, I have developed fairly constant lower back and neck stiffness/pain. These problems had gotten so bad, I began questioning whether I could continue in this line of study. Physiotherapy and Chiropractic helped, but could not solve the problem.

Then I found this incredible app!

It gently reminds me, every 15 minutes, to sit up, move my head and neck, stretch my back, etc… After an hour, it kicks me off the computer for 10 minutes to go for a walk, make some tea, do some stretches. This has done more for alleviating my back/neck issues than anything else Ive tried. I feel physically better than I have for years. Thank you!

Jeffrey Fulton about Time Out - Break Reminders, v1.6.5