I looked through amazon.de searching for CDs I wanna buy in the near future and amazon.de recommended this to me:
Footbag Book
I don't know if someone has already seen this, but I think it is quite funny.
Although the funniest part was the comment of one guy who bought this:
"A book that teaches you every footbagtrick existent. If you are a footbagger - buy it!"
It has 43 pages, so the font must be really small

But I was positively surprised of the use of 'footbag' and not hackysack.
greets