Take an IP and try to look for the domain/host associated with it.
Get approximate IP details.
Get all possible details about an SSL certificate.
Get all possible details about a domain name.
Ping a website, server or port..
Get the gravatar.com globally recognized avatar for any email.
Extract email addresses from any kind of text content.
Check if the URL is cached or not by Google.
Encode any string input to Base64.
Convert text to binary and the other way for any string input.