Workrave is a program to help prevent repetitive strain injury (RSI) by alerting you to take breaks of various duration throughout the day.
I didn't write any part of this program so go to the workrave website for more details.
RPM for Fedora Core 4
I haven't found an RPM of the latest version for FC4 and it is tricky to build as it has quite a few depenancies so I have put my RPM's of the program here. However all the packages that this depends on are either in Fedora or in Fedora extras.