Joost Disk Space Hunger
Joost, the revolutionary online TV service, is the new craze on the Web. However, if you have been using it extensively, you may have noticed that you are running out of disk space. Ouch!
Not sure how it behaves on Windows, but on OS X, Joost demonstrated an early bug - it “eats” disk space through thoughtless caching. Hopefully, Joost guys will fix the problem, in time, but for now, unless you have unlimited disk space, make sure that you periodically delete:
~/Library/”Application Support”/Joost/anthill/anthill_cache under your home folder.