Apple have recently published a guide to the policies on iPhone 3G carrier locking around the world.

The guide helps to detail the countries where the iPhone 3G is not locked to any carrier, these countries include Belgium, Greece, Taiwan and the Czech Republic (amongst others).

In the countries where the iPhone 3G is not locked to a carrier consumers have the ability to purchase the handset and use it anyway they wish - on any carrier.

[via support.apple.com]