Hi guys,
I figured this list would have enough blockchain enthusiests here
that it would be worth mentioning this project. A few months ago
I was tasked by XWiki SAS Research to develop a realtime
collaborative editor which could do text, WYSIWYG and collaborative
drawing. I decided to do it using a peer-to-peer consensus algorithm
using a Nakamoto Blockchain with the difficulty/mining aspect removed.

AFAIK this is the first application to use a blockchain which has
nothing at all todo with bitcoin.

Javascript - LGPL-2.1
https://github.com/xwiki-contrib/chainpad

An early use of the algorithm:
http://extensions.xwiki.org/xwiki/bin/view/Extension/RtWiki


Thanks,
Caleb