I'm familiar with fzf and it deserves more love if you're a shell user. Essentially it's a completion/selection framework. You pipe potential options to it and it helps you narrow/select them.
What that looks like is, you hit C-r in your terminal, and it shows you all of your history and you can start typing to narrow the command you're looking for.
The other thing it does, is say you're looking for a while, but you don't really remember where it is. Hit C-t and it'll pop up a completion interface that has all of the files from the local directory. Then you can narrow it down to the files you need and dump it into the command line. It's very fast.
This is just a subset of what it can do, because it integrates with Emacs and other editors.
GNU datamash - handy for field processing like collapse, sum, etc (instead of awk/perl)