Grayscale-friendly cheatsheet 
The cheatsheet is very handy, but I think that a typical use case is that people print it out (like I did) on a black and white printer. When the document is rendered in grayscale, the colours are barely distinguishable, so the graphical examples are difficult to understand.

Perhaps the cheatsheet could also exist in a grayscale-printer-friendly form, which uses fill patterns in the cells, rather than colours? Or maybe the cells could contain some symbols to help differentiate them?

I could give it a shot, if others agree that such a need exists.