It seems to be somewhat abated, now, but for most of yesterday and today you could not access any of my sites due to traffic issues.
I traced what I think was a “race” situation from one of the spam robots spidering the sites. It used some odd get parameters and my permalink finder plugin was getting confused. I had fixed this a few weeks ago, but I never distributed the plugin so it started happening on some of my domains where it had not occurred before.
I uploaded the new plugin and the storm seems to have passed. I am not getting thousands of hits on the same web page in the space of a few seconds.
I now have to clean up the plugin and publish it so other sites can use it.