graeme_p - 9:58 am on Jan 9, 2010 (gmt 0)

I'm not sure I agree with that in all cases. What about expats from that country living/working abroad?

As one I think this is important! There are lots of people in this position: 10% of British citizens, for example.

In addition, the people you want to deter with restrictions will find ways around it, unless you have really tight restrictions (like .lk for example) but that ends up blocking legitimate use as well.