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