Google Drive lets you  store your files, share files with exactly who you want and edit them together, from any device. Google Drive gives you instant access to Google Docs, a suite of editing tools that makes working together better—even when your teammates are miles away.



http://docs.google.com

ThinkFree online is a free web office service that allows document editing via online access, without having to install any application. You can save documents that were created by web office into MyOffice, share it with friends, or collaborate via "Workspace", which allows users to steamline group projects. 



http://member.thinkfree.com/member/goLandingPage.action

Codepad is an online compiler/interpreter, and a simple collaboration tool. you can paste your code , and codepad will run it and give you a short URL you can use to share it in chat or email.



http://codepad.org/

Teaching demands a fine balance between letting your students do, and showing them how.

Collabedit allows student and teacher to share a common workspace without the distractions that other tools impose.

You don't need the hassle of exchanging emails with bad formatting. Whiteboards do not work very good for code, neither does Power Point. The pain of saying "closing parenthesis" out loud is no longer necessary.



http://collabedit.com/

MeetingWords is a simple text editor for the web. Your text is saved on the web, and more than one person can edit the same document at the same time. Everybody's changes are instantly reflected on all screens. Work together on meeting notes, brainstorming sessions, homework, team programming and more!



http://meetingwords.com/

Write together in real-time with Basecamp text docs. Brainstorm ideas together. Write a press release together. Collaborate on a blog post or a company newsletter.



http://basecamp.com/write-together