Having a treadmill desk is great, but not everyone has one. You can also set the computer on a pedestal so that you stand while on the computer, but if you want something simpler and easier to use, consider Fade Top– it’s a visual break reminder that reminds you to get off your butt and do something.
It’s a free download, that’s small and basic to install. Once installed, it will fade the computer at specifically set intervals, to remind you to get away from the computer. You can change settings to different colors, messages, and even timers.
What I like about this, is that you can continue to type, and control the amount of ‘fade’ to your computer screen. This way, if I’m in the middle of something, I can still finish without having to drop everything.