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..
Easily convert PNG image files to JPG.
Easily convert megabits (Mbit) to zebibits (Zibit).
Find A, AAAA, CNAME, MX, NS, TXT, SOA DNS records of a host.
Make sure your passwords are good enough.
Reverse a list of given text lines.