CoSketch - CoSketch is a multi-user online whiteboard designed to give you the ability to quickly visualize and share your ideas as images. No registration or plugins required.
ClickMeeting - Collaborate with partners and clients using ClickMeeting professional web conferencing software. Try it now, FREE!
IDroo - A shared whiteboard for use by multiple Skype-users simultaneously. Features
Onstream Media - Onstream Media is a video conferencing software that facilities businesses operations for different industries.
Scribblar - Scribblar is a free online collaboration tool that is perfect for online tutoring.
GoToWebinar - Webinar & Online Conference | GoToWebinar