Tools.Office - Tool online that allows to create, to share and to publish spreadsheets, text documents and presentations

Looking for material for a development I found this tool of very interesting Google that is called Google Docs => http://www.google.com/google-d-s/intl/es/tour1.html

Básicaly consists of a tool online that allows to work with (to create, to modify, to share) lists of calculation, text documents and presentations.

It is free to use, only need google account.