I heard so much about this book "Thirteen Volume One", and in particular "The Magic", which is the story you are referring to.
I must admit, at first I thought the whole thing was just a publicity stunt and didn't think it could be that scary. Eventually curiosity got the better of me and I downloaded it for five bucks onto my PC via Amazon. I am a grown man, I must point out, and I can honestly say I have NEVER read anything so scary. It really got to me. The story isn't a story in teh trasditional sense - it's more of a dare. Difficult to explain without giving too much away, but I thought it was genius.
A lot of the other stories are pretty freaky too, but 'The Magic' is the scariest so far (I'm about half way through the book).
Good luck if you do decide to read it.