Glare on your computer monitor is more than just an annoyance. It can leave you with eyestrain and a headache. Taking the shine off your screen should be an ergonomic priority.
Evaluate your computer setup to determine whether the monitor is optimally positioned. You don't want the screen to be facing a window, nor do you want to be facing a window yourself--a position that can cause eyestrain from too much light contrast. The ideal screen-to-window angle is 90 degrees.
Video of the Day
Reduce the amount of bright sunlight in your workplace. Shades, blinds and draperies all help block sunlight. Even switching to a flat rather than glossy wall paint can help.
If you have a bright light source directly above your screen--the worst possible place and typical of many offices--try turning it off and placing a small desk lamp to one side of your computer instead.
If you can't avoid overhead light, you can construct an anti-glare hood for your monitor by taping together several sheets of black cardboard and using them to frame your monitor screen.
If you can't avoid bright light from a window (or if you think a hood looks too goofy), purchase an anti-glare screen to place over your monitor. Generally, the best ones are polarized or have a purplish optical coating.