I discovered this somewhat recently...

http://ip-to-country.webhosting.info/book/print/5

Its a list of all the IP codes around the world and to which physical country they belong. So I wrote a perl script to convert the CSV file and a set of named countries into a list of htaccess blocking codes. So I can block my website to people and proxies from a particular country.

I thought the link interesting enough to post - if you want the perl script then shout below. Its not extremely well tested but I dont appear to be having as much ukraine / latvian hacks since I added it. Though I am not known for posting code, I thought this one good to share if required and maybe if enough people took a more proactive filtering of their sites then maybe they would have less ability to hit them so much - wishful thinking I am sure !