Try the Shaggymac Swiper, it is made from the exact same material.
We use these to wipe down 30" Cinema Displays in our AV room and they work incredibly well!
Anthony- I know that exact feeling.
I would seriously just go to your local Apple Store and ask for one. One time I went because my earphone jack was falling off, they went in the back and got me some new ones. I'm pretty sure they won't charge you for such a small and thin cloth like that.
Step 1: untuck shirt
Step 2: turn screen towards torso and press phone against body
Step 3: rub up and down furiosly like you are trying to start a fire
Step 4: check screen, repeat as necessary until clean.