Take an IP and try to look for the domain/host associated with it.
Find A, AAAA, CNAME, MX, NS, TXT, SOA DNS records of a host.
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..
Extract email addresses from any kind of text content.
Check if the URL is cached or not by Google.
Use the Google translator API to generate text to speech audio.