I've gotten about 8K head requests today from a very wide network of machines in hosting centers that I assume may be compromised.
All user agents in this attack were the same:
"Mozilla/5.0 (Windows NT 5.1; rv:6.0) Gecko/20100101 Firefox/10.0.2"
Looks like a failed DDOS doing 500-600 requests per second and my site monitoring system never went off so they obviously didn't slow it down enough to cause any failures.
Amazing what a dual quadcore can do :)
I'll see if there's anything interesting to report after I process the log file.