http://cht.sh/ - I use this a lot. It outputs a short summary of common commands for many cli tools. You can curl to it https://cht.sh/grep for example or install their cli client
Glad you found it useful. It has become one of the things I install when I setup a machine.
Being able to use curl as a client as well is so powerful as well. Whenever you are using ssh on some vps you can still get cheatsheets for all your commands.
