I am a big fan of objectively ranking consumables.
Ritter Sport flavors. This database was created over a 6-month time period that I spent visiting the ML ITP Heidelberg group. I know that the list is not complete and that there are very niche flavors that I could not find (even after a trip to the Waldenbuch factory!). I will pay very good money to anyone who can get me a flavor not listed.
Cafes in Berkeley. A growing database of all the coffee shops in the Berkeley area. It is still growing, but I hope to be done with it by May 2025.