Just after the iPhone 3G S is launched with iPhone 3.0 firmware which is the latest OS for the iPhone, the dev team has released the first tool to unlock the 3.0 firmware with the help of Pwnagetool which is currently available for Mac OS X. Windows users should have to wait for the same tool to be launched for their OS.

As always, the Dev Team comes with some rules for the users to try out the unlocking tools, here are those -
GOLDEN RULE: If you are using a 3G iPhone with yellowsn0w and rely on yellowsn0w to obtain cellular service, then you should NOT use PwnageTool right now. UltraSn0w is not included with this release and therefore your baseband will be locked and unable to use an operator other than the official one it was bought for. UltraSn0w will be release via APT (cydia and icy) soon. If you have an original iPhone (1st generation) then 3.0 unlock works with this PwnageTool release.
PwnageTool WILL work for Original iPhone (1st Generation), Original iPod touch (1st Generation) and the iPhone 3G.

It is not to work with the iPhone 3G S which is just launched.
Check this post to learn everything about the Pwnagetool for unlocking iPhone 3.0.

Here are a few mirror links to download the Pwnagetool for 3.0 firmware of iPhone -

• http://www.revotech.org/mirror/PwnageTool_3.0.dmg
• http://www.istation.at/pwnagetool_3.0.dmg
• http://neon.hexxeh.net/PwnageTool_3.0.dmg
• http://www.itouchmaster101.com/PwnageTool_3.0.dmg
• http://www.zackoch.com/iphone/PwnageTool_3.0.dmg
• http://just.legalizecanna.biz/PwnageTool_3.0.dmg
• http://www.neonkoala.co.uk/files/PwnageTool_3.0.dmg

Btw for those who were trying out the iPhone 3.0 Beta 5 firmware, were able to unlock the iPhone with QuickPWN 3.0 beta 5 version, but that does not work with iPhone 3.0 firmware, so the dev team would probably come out with the new version of Quickpwn for both mac and windows to unlock the 3.0 firmware.