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.
Get the gravatar.com globally recognized avatar for any email.
Get approximate IP details.
Find A, AAAA, CNAME, MX, NS, TXT, SOA DNS records of a host.
Make sure your passwords are good enough.
Check if the URL is banned and marked as safe/unsafe by Google.