It's the latest news from the iPhone Dev Team: they have released their latest tool, Ultrasn0w, which unlocks the iPhone 3G for use with any carrier. And it also works in conjunction with the Team’s Redsn0w app, which is first used to jailbreak the iPhone 3G, and can unlock the latest iPhone OS 3.0 software. However, Ultrasn0w does not work yet on the new iPhone 3GS.

Here is how Ultrasn0w works for iPhone 3G:

1. Ensure you have upgraded to iPhone OS 3.0
2. Jailbreak your iPhone 3G using redsn0w or PwnageTool (this will also install Cydia/Icy)
3. Run Cydia or Icy
4. Please add the repo repo666.ultrasn0w.com to Cydia or Icy.  That last “o” is actually the number zero “0”! If you use the letter “o” you’ll get an error.
5. Search for ‘ultrasn0w’ in cydia or icy and install ultrasn0w
6. Reboot your iPhone 3G
7. T-Mobile USA users should disable 3G before using ultrasn0w
8. Enjoy

[via SlashGear]