If, like me, you partially got the iPad to write on and don't like writing with your finger, you probably own a stylus. And given how few cases come with stylus holders, like me you probably don't use it as much as you'd like to because it's hard to keep it with the iPad.
Zoogue is now offering "free" stylus holders - the true cost is only $2 shipping. Of course, they are made to work with Zoogue cases, and so they may or may not work with yours. But $2 is a pretty minimal investment to find out, and now that I've got mine I can copy the design with a thinner sheet of plastic that will fit in my case.