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.
Upload a QR code image and extract the data out of it.
Convert normal text to old english font type.
Make sure your passwords are good enough.
Find A, AAAA, CNAME, MX, NS, TXT, SOA DNS records of a host.
Convert text to hexadecimal and the other way for any string input.