If you watch what architects actually do when they design, you'll see that all of them draw to think. At the wiki hangout I shared a bunch of past projects experimenting with ways to draw in browsers. Here I collect the links with the intent of expanding this into a wiki of its own.
Architects aren't alone in drawing to think. See Flexible Sketches Inflexible DBs
See also Incorrect and Still OK Diagrams
We used drawing as a toy problem to explore different ways of understanding generators and observables. See Javascript Generators, ObservableHQ Observable, and RxJS Observable
//dobbs.github.io
HEIGHT 1400
dobbs.github.io 
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javascript turtle graphics ,
logo and fractals to learn recursion
Screenshot of work in progress on Secure Cooperation Picture Book
Re-drawing diagrams was a way of deepening my understanding of object capabilities. See Secure Cooperation Picture Book
Here, building apparatus widgets to support the construction of sequence diagrams. Building these models in apparatus allows me to think more deeply about what dimensions to control in a sequence diagram (in this case, controlling time)
//apparatus.wiki.dbbs.co/?load=saves/Sequence.json&fullScreen=1&viewOnly=1&editLink=1®ionOfInterest={"x":[-5,6],"y":[-3,4]} HEIGHT 270 Sketch of messages arriving out of order.
It's also a very old idea. visual eucild's elements
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David suggested p5js.org
Observable lends itself to lots of experimentation too.