Convert text to binary and the other way for any string input.
Convert text to ascii and the other way for any string input.
Convert text to decimal and the other way for any string input.
Convert text to octal and the other way for any string input.
Extract email addresses from any kind of text content.
Get all possible details about an SSL certificate.
Get all possible details about a domain name.
Get approximate IP details.
Find A, AAAA, CNAME, MX, NS, TXT, SOA DNS records of a host.
Take an IP and try to look for the domain/host associated with it.