I just checked out that greek disk site. It's a cool idea, but really works better for fraternitys than sororities. With NPC formal recruitment you can't give the PNMs anything to take home, unless you did a generalized panhellenic one.
What would be cool is to have one made each year, kind of like a 'yearbook' for the chapter. A great way to keep a running history of the chapter as well. And when you graduate you have all 4 years on 4 CDs-the box set!
