Minify your CSS by removing all the unnecessary characters.
Minify your JS by removing all the unnecessary characters.
Extract email addresses from any kind of text content.
Take an IP and try to look for the domain/host associated with it.
Convert markdown snippets to raw HTML code.
Convert forum type bbcode snippets to raw HTML code.
Check if the URL is cached or not by Google.
Get the web-host of a given website.