Blocking foreign countries from your proxy site

I wrote a guide on how to do this with GeoIP. This is particularly a good idea in my opinion because adsense will pay more if you filter the foreign traffic. You can redirect all the foreign traffic to another site that hosts different CPC ads or whatever suites you best.

http://www.samdaves.com/blog/2007/0...-specific-countries-from-accessing-your-site/