PAT2004  This program was recommended to me. I have chronic dry eye and am nearsighted and being at my iMac all day aggravates both of these. Time Out has two different kinds of breaks.There's a short break - I use that to just look away from my computer every 10 minutes for 10 seconds. The main break is long enough to get out from my chair and away from my iMac to stretch for 10 minutes. You can set either of the short or long break to take place at any interval you want FOR any time you want. Sometimes if I'm working on an article I choose to "skip" the break not to lose my train of thought. This has greatly reduced my eyestrain and helped improve my dry eyes.  
(Version 1.5.2)