iPhoneDevWiki has posted the first versions of an easy to use GUI version of the SIM unlocking tool that has been circulating on the internet.
This new version needs only be copied over to the phone and executed, it's full automatic. No more needs for fls or extract bin files out of the nordump. It should also cut the time down to max. 3-5 minutes.
If successful, the tool should unlock your iPhone so that you can use any network's SIM card for service. A number of commercial solutions had previously been mentioned.
This appears to be a very early version and anecdotal reports have had mixed results, so you should proceed with caution at this time.