I have many times wished that each little square in the editor's font colour selection drop down could have title attributes set to the colour names. It would help reduce the number of times I have to try again to get the right color.

Now it has dawned on me that it must be even worse for the colour blind. A color blind person might not know what a particular color looks like, but still might know that custom dictates red text indicates one thing, blue text something else, green text a third thing.

These colour blind simulations should give an idea how difficult it is to pick the desired colour without the help of the title tags (aka "tool tips").