List of free thinking stuff for developerππ½
If you're looking for all programming tools around thinking (not just free). Check this page List of thinking Programming Tools

Lucidchart
Lucidchart is the intelligent diagramming application where seeing becomes doing. With this intuitive, cloud-based solution, everyone can work visually and collaborate in real time while building flowcharts, mockups, UML diagrams, and more. Sign up for free now.
Tag: thinking, collaboration
Team collaboration 100 Professional templates