Google is a search engine for human readable content. Shodan does the same for machine readable content.
You can:
- search for specific IP addresses, and it will show you the active ports, and running services.
- search for a specific response header in the set of countries
- browse through the screenshots of open VNC & RDP
- open webcams
- and more...
The free accounts can use any feature, but the list of results is limited. But if you really want to look under the deck of the internet, the subscription is worth it.
I'm not affiliated with the company in any way, there's not even a reflink. I just find the service useful and fun.
At first I wasn't sure whether to post it here or not, but since it's certainly more tech related than the business model of twitter and reddit, which is being discussed here pretty often, I decided to go for it.