This article is from the Ergonomics and Typing Injury FAQ, by Dan Wallach firstname.lastname@example.org with numerous contributions by others.
A. Frequently used items should be within arms reach from your keyboarding
position. A document holder should be at the same height and distance as
he screen so that your eyes don't need to change focus frequently.
Frequent telephone use should utilize a headset to avoid bending the neck
while keyboarding. Remember that many RSI's begin with nerve insult in the
neck and shoulders.