Make sure your passwords are good enough.
Find A, AAAA, CNAME, MX, NS, TXT, SOA DNS records of a host.
Get all possible details about an SSL certificate.
Get approximate IP details.
Take an IP and try to look for the domain/host associated with it.
Easily convert IDN to Punnycode and back.
Convert your text to any kind of text case, such as lowercase, UPPERCASE, camelCase...etc.