"Mapping the net" did we call our little project to map as many known hosts, ips and domains as possible some two years ago. Some laughed, others smiled. And we mapped. Thousands of hosts daily, running into a steadily growing postgresql-database built out of junk-hardware, running on a single cheap dsl-connection.
I started some bencharking using search-engines to see how many hosts we really know, and i was surprised to see that we already know between 70 and 80 percent of all known hosts of major international hosts indexed on rank 1-1000 in common search-engines. And we've still far more than 10 million hostnames listed to sort in. I didn't expect to get so far when i started this funny project.