I'm in the process writing my own version of webscript.io, an old service that died back in 2017. It was a dead simple service that would run a Lua script for each HTTP request that came in to a URL. It sounds pretty trivial, but it was remarkably useful for hacking together little scripts for things like watching webpages for changes, little custom APIs for DIY IoT devices, translating from one API to another, and other simple stuff like that.

I've got enough of it built that I've been able to make a few actually useful things with it already. A few different job posting website scrapers were the first thing I made. I also made a little script that queries a live traffic api and sends my wife an estimated drive time for her commute home. The plan with that one is to watch the drive time as it's getting closer to the end of the day and if it starts spiking earlier/worse than normal, it can email her letting her know she should leave early if she can.