[texhax] Collaborative editing: Latex

[Tom Backer Johnsen]

Some colleagues and I are collaborating on a book project using Latex, 
and it would perhaps be nice to use some web-based tool.  I came 
across one in a web page or magazine some time ago where the 
illustration was Latex.  I promptly forgot/stupidly to make a note of 
it at the time.  Are there anyone who can jog my memory or make a 
suggestion?

Tom