draw.io - Online diagramming application
Phontabulous - Fun, private, secure photo party with your friends
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.
Vecihi - Build your own photo sharing app in 5 minutes
PlantUML - PlantUML is an open-source tool that uses simple textual descriptions to draw UML diagrams.
100 Days of Wordplay - 100 Day Project - 100 mini crossword puzzles