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.
Get all possible details about a domain name.
Ping a website, server or port..
Get the web-host of a given website.
Get details of any file type, such as the mime type or last edit date.
Check if the URL is cached or not by Google.
Parse details from user agent strings.
Extract email addresses from any kind of text content.
Convert pounds (lb) to kilograms (kg) with ease.