A very useful tool to have on one's internet utility belt. Shades of nslookup, dig, netcraft, & pingdom all rolled up into one handy little extension. Thank you Shodan, well done. Also a smart, honest, & excellent way to promote one's APIs. @john knight: i find you might have to wait a few to tens of seconds at times for the data to return. It seems the extension does its gathering in near real-time. Useful for freshness, but does require more patience than you might be used to. :)
The Shodan plugin provides information on website hosting, IP ownership, and open ports
It also offers network monitoring capabilities for real-time notifications of unexpected network activity