Whether you have a Mac or a PC then you will most likely benefit from calibrating your screen. For the Mac, you can use software such as SuperCal. You will only need to spend about 10 minutes with the software and follow the simple on-screen instructions and the software will create a new display profile for you. The display will then be calibrated personally for yourself and how you perceive different colours etc.
If you are unsure about the change, you can go to System Preferences>Displays and select the color tab. Here you can compare the profile you have just made to the predefined ones that come with your Mac and view the changes instantly. After making a new profile my 12″ powerbook screen seems less washed out and has richer colours!
SuperCal can be used for free but it is shareware and so you are encouraged to buy a license for $19 if you find it useful.