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..
Make sure your passwords are good enough.
Find A, AAAA, CNAME, MX, NS, TXT, SOA DNS records of a host.
Convert miles per hour (mph) to kilometers per hour (kph) with ease.
Convert your HEXA color format to RGB format.
Use the Google translator API to generate text to speech audio.