Here's a list of various sites:

Dreamweaver: http://www.adobe.com/products/dreamweaver/

Skype: http://skype.com/intl/en/welcomeback/

SecondLife: http://secondlife.com/

Elluminate: http://www.elluminate.com/live/d.html?ck=QCKB7U1Y&ref=1

Moodle: http://www.sloodle.org/