I needed access to a toggling value for an automation. I could have written a local file or use a local data store but I was inspired to make a simple web service instead.
swap.ist gives you URL key that whenever accessed will toggle between true or false.
The use-cases are... at least one, but probably more.
1) Node Express Server 2) Using Firebase RTDB to store swap state 3) CloudFlare Tunnel to a web-server I had laying around
index.js is 141 lines, including the HTML for the homepage.