Cheat sheets or reference cards for Mathematica

Here are two I have found:

Mathematica Quick Reference

Mississippi State University Mathematica Guide

I'm not sure these are great but they are the best I've found. (I take it these are along the lines of what you want, correct?)

Best Cheat Sheet so far...

Pretty much the best Cheat Sheet I have come across so far, is the following one by Hugo Touchette, a theoretical Physicist teaching at the National Institute for Theoretical Physics, Stellenbosch, South Africa:

Mathematica commands summary

The sheet has been last updated in May 2016 (Mathematica 8), but does need some updating for later versions. There is btw also some useful $\LaTeX$ - Information to be found on his pages...