Awareness is described as 'helps you become more aware of time spent on the computer'. There are more than 10 alternatives to Awareness for a variety of platforms, including Windows, Mac, Linux, Online / Web-based and BSD. The best alternative is stretchly, which is both free and Open Source. Other great apps like Awareness are Workrave (Free, Open Source), Eyes Relax (Free), Eyeleo (Free) and Iris (Freemium).
stretchly is cross-platform open source app that reminds you to take breaks when working with computer. By default, it runs in your tray and shows reminder window every 10 minutes, that is open for 20 seconds, containing idea for microbreak.
Workrave is a program that assists in the recovery and prevention of Repetitive Strain Injury (RSI). The program frequently alerts you to take micro-pauses, rest breaks and restricts you to your daily limit.
It’s an utility that helps avoiding eyes-related problems when working at a computer for several hours. Concentrating your eyesight on a computer screen can cause an eye strain. You can prevent this by taking regular breaks during the work and look at distant objects.
EyeLeo is a handy PC application that reminds you to take a break for your eyes. Features: Screen blocking long breaks every hour. Short breaks with eye exercises every 10 minutes. Eye exercises shown by an adorable Leopard.
Iris is software which makes monitors healthy for the eyes. With iris you can reduce the blue light emitted from your screen for better sleep, reduce the brightness of your screen without PWM and avoid eye pain.
RestStop sits in your tray and gives you non-intrusive reminders to rest after you’ve worked continuously for awhile. It looks like an hourglass, and it fits right in with the other Windows tray icons.
Time Sink helps you track how you spend your time on your Mac. It automatically logs opened windows and applications, and keeps track of how long you've spent using things in total (i.e. running), and in the foreground (i.e. actively using).