draw.io - Online diagramming application
Onstream Media - Onstream Media is a video conferencing software that facilities businesses operations for different industries.
LucidChart - LucidChart is the missing link in online productivity suites. LucidChart allows users to create, collaborate on, and publish attractive flowcharts and other diagrams from a web browser.
ClickMeeting - Collaborate with partners and clients using ClickMeeting professional web conferencing software. Try it now, FREE!
PlantUML - PlantUML is an open-source tool that uses simple textual descriptions to draw UML diagrams.
GoToWebinar - Webinar & Online Conference | GoToWebinar