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 ascii and the other way for any string input.
Convert text to octal and the other way for any string input.
Make sure your passwords are good enough.
Get the gravatar.com globally recognized avatar for any email.
Get approximate IP details.
Find A, AAAA, CNAME, MX, NS, TXT, SOA DNS records of a host.
Check if the URL is banned and marked as safe/unsafe by Google.
Easily remove duplicate lines from a text.