If you haven't been reading
The Onion Router FAQ recently then you may have missed the fact that you can now specify which country or countries you would like to use for your entry or exit nodes. In Tor versions older than 0.2.1.x the way to get this effect was to enter a list of nodes from your country of choice. This manual method was tedious and the nodes specified were soon outdated, so this improvement will make for more robust and easier country restrictions.
If you would like your internet traffic from a computer outside the United Kingdom to appear from within the UK, for example, you would edit your
torrc file to contain the following two lines:
ExitNodes {gb}
StrictExitNodes 1
A trap for new players is that the country code used differs slightly from internet country codes. Tor uses
ISO 3166, in which the UK is denoted "gb" instead of "uk".