Pangur

an example of pangur - a collection of boxes joined by curved lines, overlaid with poetry

Pangur is a visual programming language for working with text in real time.

Try Pangur
Look at an example or two
Read the Pangur Primer

Pangur has been developed using Firefox and tested using Chrome, both on a Mac. If you're using another browser or operating system, it may work, but no promises. It may also break if you're using the same platform as me, but I will be more sympathetic in that case.

Pangur was made by Martin O'Leary/@mewo2