Here's another package suggestion. If there's already an ergonomic program in the Vector Linux repository that does this job, please let me know.
Xwrits is an ergonomic program that reminds the user to take breaks and wrist rests regularly.
Source and documentation is at:http://www.lcdf.org/xwrits/
The only other Open Source ergonomic program I know for Linux is Workrave (available at Sourceforge). Workrave does more (including displaying exercises), but Xwrits seems to use less resources and works well on lightweight systems (which may be useful for Vector Linux Light users).