You knew it was only a matter of time before someone unlocked the T-Mobile G1. Well it has happened as you can see in this video.
Unlock-TMobileG1.com is offering unlock codes for $22.99.
"After placing an order including your IMEI code you will receive an eight-digit unlock code for your device. Your IMEI number can be found by pressing *#06# in the dialer, or by going into your settings, selecting �About phone� and then selecting 'Status'. The IMEI number then can be found about half way down, it is 15 digits long."