This service describes itself as “the closest thing to paper-and-ink editing on the Internet”, and it acts as an interesting alternative when it boils down to collaborative text edition on the WWW.
Revizr makes for passing documents to others and letting each individual write comments and corrections on it.
Each person is assigned a different color, so that you can always see who suggested what and when. Should changes be made, e-mail notifications are sent.
As the document owner, you are given the option of choosing who has actual access to your document. It can be open to all and sundry, or it can only be accessed by an individual or a group of people. In any case, the owner of the document is the one who has the final word, as nothing will be modified until he approves the change itself.
This solution is entirely browser-based, too. In practice, that means that any person who has a web-enabled computer can collaborate on any document, without having to worry about compatibility issues and related concerns.
Revizr.com In Their Own Words
“The closest thing to paper-and-ink editing on the internet.”
Why Revizr.com It Might Be A Killer
It is a free tool that does its job in a timely manner.
Some Questions About Revizr.com
What are the requirements when it comes to uploading a file? Do you have to upload plain text files, or can you upload rich files? 
