I've recently experienced a canonical instance of the Baader-Meinhof Phenomenon. Until the other day, I had no idea that Emacs had a built-in spreadsheet. Now, I'm seeing references to
ses (Simple Emacs Spreadsheet) everywhere. It even has its own manual.
I use Org-mode tables and Babel for that sort of thing but it's nice to see that if you really want a spreadsheet, Emacs has one for you. One of the nice things about
ses is that you use normal Elisp to calculate cell values. That give you both familiarity and flexibility.
This discovery probably isn't life changing but it is another example of how Emacs always has something new to show you. If you want to try it out, type 【Meta+x】
ses-mode in a new buffer.