KenB - 10:55 pm on Feb 17, 2010 (gmt 0)
One thing to remember about banning countries based on IP addresses is that IP address ranges do get reassigned from time to time. As such any static solution like a .htaccess block list will become outdated over time. In the short run it takes a little work to set up, but in the long run the easiest to maintain method of blocking would be using a geo IP database/CSV file to convert IP address to country code via PHP (if you are using PHP) and then block/allow based on the resolved country code. Then when it comes time to update your IP address data all that is required is to drop the new data into place.