RetailMenot - The RetailMeNot mobile app allows you to find deals on the go for both online shopping and in store shopping.
draw.io - Online diagramming application
Slickdeals.net - Slickdeals: The Best Deals, Coupons & Discounts on everything
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.
Honey - Honey is a browser extension that automatically finds and applies coupon codes at checkout with a single click.
PlantUML - PlantUML is an open-source tool that uses simple textual descriptions to draw UML diagrams.