SmartDraw - Instead of starting with a blank screen, SmartDraw gives you the exact template you need.
Diagramo - Diagramo is an online flowchart software - diagrams (create, edit and share)
Signavio - The Signavio Process Editor was created in order to be very intuitive and easy to use.
Modelio - Modelio is an open source modeling tool supporting natively UML, BPMN and model exchange with XMI.
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.
ARIS Express - ARIS Express is based on the proven ARIS methodology and industry standards.