Filter option is nice too, here's top `awk` commands: https://www.commandlinefu.com/commands/matching/awk/YXdr/sor... (expected removing duplicates to be #1 instead of #3)
There are comments too, but some are filled with spam.
See also:
* http://www.compciv.org/unix-tools/
* https://github.com/jlevy/the-art-of-command-line
* https://github.com/learnbyexample/scripting_course#ebooks (my books on grep/sed/awk/perl/ruby/coreutils/etc - free to read online)