Tunneling IP over DNS - Dan Kaminsky's ozymandns project. One source of really strange DNS packets I've seen is Dan Kaminsky's experiments with tunneling IP over DNS , which he presented at Codecon, Defcon, and other places. Dan has often done Really Twisted Things With Packets, and once you've already tunneled IP though HTTP, it's time to do something a bit more aggressive. His first implementations were relatively straightforward, good enough for using SSH and email from the DNS servers on random wireless access points without needing to log in, but they weren't really high performance. The work he demonstrated at Codecon 2005 was able to do high-performance streaming video over DNS, which required spreading the data stream over tens of thousands of DNS servers. It was quite impressive, in a this-is-seriously-wrong kind of way. Perhaps somebody's running something like that somewhere near you.