"Distributed web host CloudFlare says its costs rise dramatically..."
Don't let them hear you say the dreaded words "web host." Cloudflare serves up huge quantities of spam sites, malware, and phish sites...but its abuse team will quickly point out "we are not a Web host and therefore we will not/do not have to/cannot take any action against abuse on our network, now be off to bother someone else" if you file an abuse report.