Convert text to binary and the other way for any string input.
Convert text to hexadecimal 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.
Get approximate IP details.
Get & verify the meta tags of any website.
Get all possible details about an SSL certificate.
Find A, AAAA, CNAME, MX, NS, TXT, SOA DNS records of a host.
Get all the HTTP headers that an URL returns for a typical GET request.
Take an IP and try to look for the domain/host associated with it.