VisiBL is a visual browser for IP DNSBLs and DNSWLs.
You can get to it from any feedset view page.
If you query an IP address (say, 192.0.2.3), and then click on "VisiBL: view", you will see a grid of all the IPs in that class C network, 192.0.2.0/24. Each cell represents a single IP address. Overlaid on each cell are indicators showing which DNSBLs have flagged which IPs.
VisiBL is useful for research purposes. It shows you which DNSBLs have flagged the IP you searched for, and its immediate network neighborhood.
Suppose you run your own blacklist and are thinking about blocking an IP. Karmasphere will show you what others think of that IP. VisiBL will show you what others think of all of its neighbors as well.
Or maybe you run mail servers and you're worried they might be blacklisted by someone else. If your neighbors are blacklisted, you might want to ask your upstream provider why.
With VisiBL, you can zoom out:
The class C view shows 256 IP addresses in a single class C network.
The class B view shows 256 class C networks. If you click "up", you will go to a view of 192.0.0.0/16. Each cell in the grid now represents a class C network. They are lit according to how many IPs in that class C are flagged by each DNSBL, as a percentage.
The class A view shows 256 class B networks.
The top-level, "map of the Internet" view shows 256 class A networks.
It was inspired by XKCD's Map of the Internet.
If you have comments or suggestions about VisiBL, you are welcome to post on the Karmasphere-Users mailing list.