Detects browser history :D theirs also buttons like "Window mode" for Firefox users who have enabled browser.cache.cache_isolation and "Blocker" for chrome users this crashes tabs by domain name the "Youtube" button may be buggy.

The network page can be used to list HTTP servers on your local network.

The Gender page can be used to detect your gender using the Ad personalization cache.

Unrelated but theirs also https://rickroll.ndev.tk/ which bypasses the chrome download limit to spam the user with lyrics.