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 decimal 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 details of any file type, such as the mime type or last edit date.
Get the web-host of a given website.
Get & verify the meta tags of any website.
Check if the URL is cached or not by Google.
Check if the URL is banned and marked as safe/unsafe by Google.