The other day we staggered across a strange botnet. It was only small as far as IP addresses were concerned, but gigantic as far as domains under management (greater than 25,000 currently in use). The cost of registering that number of domains is a significant investment by the botnet operators - at $20 each to register, you're looking at $500k in setup costs alone).
But the strangeness doesn't end there. The botnet is being used for pharmaceutical scams (i.e. Canada Drugs), but the DNS lookup process is messed up. Somehow the botnet operators have figured out how to manipulate the .com root servers in to doing some weirdness - and having them act as the authoritative resolvers for the 3LDs.
I'm not sure how this situation arose, but the criminals behind this are making good use of the flaw/exploit/manipulation. What they now effectively have is a system that prevents the good-guys from shutting down the resolution of where their scam Web sites are. Not good.
I'm still looking in to how this arose and what the real (longer-term) ramifications of this are. But its new to me and definitely in the strange/weird department.
I've posed a full blog about this botnet over on the Damballa site - Strange Bot-powered Scam Network. Take a look at whats going on.