Can I block China?

For some reason computers with Chinese IP addresses have been hammering the blog.
First they were beating on the comment script with attempts to spam all the entries.
Now they’re trying to repeatedly suck down every single page from the blog. According to Dreamhost’s stats, bandwidth on the blog has gone from around 40 MB/day to over 1GB/day as a result. It’s like they’re trying to DoS me.
For now I’ve got a Deny from All directive in the .htaccess file to just block all access until I can figure out what to do. Maybe I can find some mod_security rules to help block this crap.
Update: Thanks to Country IP Blocks, I filled up an .htaccess file to Deny all the IP blocks assigned to .cn (China). Probably inefficient, but effective. Even with an 87kB .htaccess file to process with each request, blog access actually seems to be a little faster. Guess that shows how much the blog was being hit.