This one is one that I'm a bit sad to write, as I'd actually quite like to do it myself, but realistically the amount of effort required to build it and maintain it is silly.
So: my girlfriend and I live in Brighton, and we'd like to have a dog. However, if you go on any dog adoption sites, look at the listings, find one that looks lovely, look at the pictures, watch the video, fall in love with them, you'll eventually read down to the bottom where it says "the dog must have 50 acres to roam free and never ever meet another animal ever". This makes us sad, and I feel like there has to be a better way.
What I'd like is some way to filter the dogs beforehand, so we can have relevant criteria surfaced. There are a few problems with this, though: firstly, there's no good aggregator that pulls in everything and lets you sort and filter nicely. The aggregators that I've found are charmingly retro, but don't allow this kind of thing. Secondly, there's no common system for presenting information that allows you to filter stuff in a useful way between the shelters. RSPCA display stuff one way, Dogs Trust another, etc, and that's before you get to all the smaller shelters where you're lucky if there's any structure at all.
In order to make Dogfinder, then, you'd need build the site and then set up a system to scrape listings from all the different dog shelters, and then parse the text in their descriptions to pull out any relevant characteristics we want to use for filtering. (This might actually be a decent use for an LLM, actually.)
This is probably a bonkers amount of effort proportionate to the marginal reward of "a warm feeling"—dog adoption places probably aren't going to offer you much in the way of kickbacks, though I guess you could get sponsored by some dog treats or something? It'd be a right pain to operate and maintain, but if someone wants to build this I'll be grateful.