OMFG, this is AWESOME!!!
Great work, nice method

And yeah,@eureka, it also took me a few minutes to understand how it really works.
I suggest two things:
- a bugfix in the script: use "wget -O " instead of plain wget. Otherwise wget will download the file as 'attachment.php?...', at least here. And FWIW, you can use
http://ixtab.tk/kpw_jb.zip as a stable URL.
- a simple zip file compatible with windows users, which would include only the update* and jb.sh, and a modified README.txt with Windows Line breaks.
Congratulations again!