CloudFlare will close your account if you are only using it to serve up assets like this unless you're paying for the $200/month Business plan.
http://phoboslab.org/log/2013/02/how-much-traffic-is-too-muc...
Essentially the site was just one html page that had endless scrolling and loaded hundreds of images. CloudFlare declared the site as being under a "Layer 7 Attack" even though it wasn't.