Just a small system update; we've updated the "stock image" options in the header image section.
There are a lot more images, and they are grouped by category. For those of you who don't want a big band photo as your site header, there are some interesting choices. We'll add many more in the future.
Another bonus is that they use images that are licensed under "Creative Commons". This means you're free to use the images in posters and other artwork, provided you give credit to the photographer.