Spreadsheets are Awesome

(moved this post from computerassistedthinking.com -- closing down that domain, I have way too many domain names)

Humans are not good add doing calculations. They become much better (faster) by using tools. Even simple tools such as counting stones or pen & paper move the limit of what we can compute much further. The next level was the advent of spreadsheet software, such as OpenOffice, Microsoft Excel, Apple Numbers, or Google Spreadsheets. Spreadsheets take a known metaphor, a grid, and extend it with automatically re-calculated formulas. Spreadsheets are very easy to start with, but on the other hand, they can also go pretty far in complexity. They don't dictate any structure on you - except the grid. Spreadsheets are awesome for numbers.

What is the equivalent of spreadsheet software, not for numbers, but for concepts, ideas, arguments?