Sunlight streams in from far above onto bookshelves that tower over you. There is a pleasant smell of dust and old carpet. There must be thousands of books in here - but due to the limitations of this simulated environment, you may only interact with a few:
websites and similar things
flat9 - a "tap to find bpm" tool built for rhythm game charting, or anything else where you need to be confident you've got perfect sync. A visual display indicates if your song has bpm drift, and Math that it does allows you to get a more precise bpm than other sites or get a good approximate bpm even if your tapping is awful.
The Higher We Climb The Harder We Fall - an old experiment in building the minimum possible website that requires a non-static backend. It's basically the discord counting bot, but as a website.