For some of you, your brand new iPhone 3GS came with the newest OS 3.1.3. For others, you unknowingly upgraded your OS without realizing what it would mean. Either way, we know that you’ve been stuck obediantly following the terms of your license agreement and running only authorized apps. Well, those days are finally over.

A new jailbreak called Spirit just been released and works on the latest iPhone and iPad operating systems.
The latest jailbreak was announced late last night on the iPhone Dev-Team blog.
The Spirit jailbreak is now out! Congratulations to @comex for the first userland jailbreak since the 1.x days.
Spirit provides an untethered jaibreak on those newer devices which used to require a computer nearby to finish the boot process. Spirit is able to do this because it doesn’t actually kick in until after the kernel is running.
Spirit is an “untethered” jailbreak for any iPad, iPhone or iPod Touch running firmware 3.1.2, 3.1.3 or 3.2. Untethered means that the user does not need to plug the device into their computer every time they reboot it, as opposed to “tethered”, which requires this.
This latest jailbreak works on both Mac and PC and is available free for download. The Reddit discussion of the new jailbreak indicates that Spirit works on the 3GS with the latest software updates, but as with anything of this sort, a full backup would be strongly advisable.
Spirit is not a “carrier unlock”, which allows the iPhone to be used with carriers other than AT&T, but a “jailbreak”, which allows users to run unauthorized software. If you’re wondering why you would want to jailbreak your iPhone, give Sarah Perez’s article, “Why You Have To Jailbreak the iPhone” a quick read.