The problem is usually a piece of javascript that a hacker has added to the site. It can easily be removed as long as you can find the infected files and remove the necessary code. We’re trying to figure out if this is a local occurence, or something that’s more widespread. We’d love to hear from you if you have any idea as to the source of the attacks, or encounter other sites that have been attacked. And as always, keep your passwords tough to guess, and close to the chest!