On Twitter? If you're not, you should be. If you are, make sure you're following @AmandaPalmer, @AFPwire, The @DresdenDolls, and this list which includes all of Team AFP!
I've had that pop up on a few different sites. It is spyware and the scan they are supposedly running is just dumping their spyware on you.The instant it pops up -- hit ALT F4 to close it right away (or x it out). I've ran scans multiple times after that pops up and everytime I'm clean still.
Firefox won't even let me on here. I have to use IE to get to the 'Box.#@!