Wiki Platform
SEAS hosts its own wiki platform called https://spaces.seas.harvard.edu, used by academic and administrative groups at SEAS for collaboration and sharing of ideas and documents.
For wikis related to courses please see https://wiki.harvard.edu
Source Code Repositories
See Version control.
This page is outdated.
Annotation Tools
Cool Collaborative PDF annotation tool : http://nb.mit.edu. Have your course PDF material on line, where students can enter notes, post questions and get answers!
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For a tutorial see : http://www.slideshare.net/phsoffer/piazza-instructors-presentation
Web Conferencing for Teaching
http://elluminate.com