Colorblind Web Page Filter
Colorblindness affects about 7% of the male population, .4% of females. ColourLovers has a great write up on a site called The Colorblind Web Page Filter so you too can experience this genetic anomaly.
The Colorblind web page filter lets you browse a web site and apply any one of 11 different color blind filters to see the page the same as those affected by the type of colorblindness associated with the filter.
Applying filters and then rendering a web page appears to take an extraordinarily long time, so if you give up on the web page filter, head over to ColourLovers to see some examples, like the GOOG logo above.