Change Cell Background Color Depening on Text

I am looking for a way to have the background color of a cell change depending what is typed into it. For example, if "SLK" is typed in, I want it to turn green. I have about 8 possible values that would be entered that need to change it to a particular background color. Ideally, I would like to have it so that the color isn't hard coded, but it rather pulls the color from a reference cell. That way, I can change the color of a reference cell and it will change it throughout the whole worksheet.

XL07 could do it with conditional formatting.

If XL07 is not an option, you will need to use a change event and a macro that would check all if you decide to change colors without cell modification. See http://vbaexpress.com/forum/showthread.php?t=22084