I had a thought about using Blockly to construct proofs, which would be translated to Lean code for evaluation.
A tool I made to help quickly categorise all the things in my Interesting Esoterica collection.
I had an idea about a way of modelling intervals of time and doing arithmetic with them, prompted by the question of what 'one month from now' means. It didn't really work.
I wondered how much work it would be to write a quiz system like Numbas, in Elm. The hardest part was thinking about randomising, because I didn't have a good understanding of how Elm's randomisation works.
A little tool to help Cushing try out the birthday problem with cars - how many cars should you expect to drive past before having a 50% chance of seeing the same string of final 3 letters twice?
I wanted to make interactive demonstrations of some codes and ciphers. I only got as far as doing the Caesar Cipher.
Stuff produced during the PhD I gave up on. I was supposed to be looking at computability of products of groups.
I'd just read Candide, I was full of big ideas, I thought I'd make a game about all of that. I didn't get far.