Dropbox – Sync files online and across computers
Slideshare – Hosting presentations
Twitter – Microblogging tool
YouTube – Video sharing site
Google Docs – Office collaboration suite
Wikipedia – Collaborative encyclopedia
Skype – Instant messaging/VoIP
Facebook – Social networking site
Moodle – Course mgt system
Prezi – Presentation software
WordPress – Blogging tool
Glogster and Eduglogster
diigo – Social annotation site
Blogger – Blogging tool
http://www.c4lpt.co.uk/recommended/2011.html