draw.io - Online diagramming application
Communifire - Enterprise Social Collaboration Software
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.
Bonzai Intranet - Bonzai is an intranet platform with flexible pre-built features for SharePoint and Office 365.
PlantUML - PlantUML is an open-source tool that uses simple textual descriptions to draw UML diagrams.
hub - The Hub is a versatile intranet portal and collaboration solution that boosts employee engagement and productivity in a digital workplace.