[losteverything]

And you can FAST. What else is there for quick and dirty stuff????

[goatlover]

iPython or Jupyter Notebooks, where you can whip up R, Julia, or other code in your browser, interspersed with markdown, charts and formulas.

[gglitch]

Emacs

[peatmoss]

I like to use org-tables for my spreadsheets:-D

I'm joking... mostly. That said, I really have used elisp functions on an org-tbl in anger before.

[sedachv]

There is also ses-mode (Simple Emacs Spreadsheet) that started shipping with Emacs since version 22.