Re: +1 for Linux (And sharing malware in 5 4 3) @AC
Er - I just checked debian.org and jigdo appears alive and well for Jessie downloads.
The main point at issue here is, from what I can tell from the documentation, that jigdo is not a peer to peer system - it's simply a more efficient way of getting an iso off debian or one of its mirrors. It enables you to update an iso without downloading the whole thing again.
Have a look at https://www.debian.org/CD/jigdo-cd/ and http://www.tldp.org/HOWTO/Debian-Jigdo/index.html.