Conditional format for dates past due

I am working on a sheet that keeps track of projects by date, priority, status, and other things. One thing I want to do is to add in some conditional formatting to make the dates turn red if overdue. So if I have a project that was due 6/1/12, if the project lingers past 6/1 without being marked complete (IF statement here?), then it would show as 6/1/12. My Priority list is as follows: 1. High, 2. Med, 3. Low, 4. Inactive, 5. Complete. I'd like the 5. Complete to show due in black.

After googling, I found this...but it's not quite what I'm looking for: http://www.excelforum.com/excel-gene...due-dates.html