"If the problem can be solved, why worry?
If the problem cannot be solved, worrying will be of no help."
-- A very famous Buddhist teaching by an Indian master, Shantideva.
Check out this handy article, "Five Simple Ways to Relax at Work When Stress Strikes" at Dumb Little Man. The tips can totally be applied everywhere, not just at work. :)
Have a great weekend, everyone!