After numerous teases, pod2g's "corona" exploit has finally come to Apple's A5-powered devices. The news will come as a relief to many as the iPhone 4S has taken longer to be jailbroken than any other iOS device. The release of a jailbreak for the iPhone 4S and iPad 2 means that every Apple product running iOS now has the potential to access Cydia, and its numerous apps and tweaks.
French hacker pod2g first announced that he'd found a bug within iOS 5 that could lead to untethering back in November, and a month later he uploaded a video of his exploit in action onto YouTube. After the public release of an untethered jailbreak for A4-powered devices three weeks later, a veritable "dream team" of iOS developers and security researchers has focused its attention on bringing the jailbreak to Apple's latest iOS devices.
Chronic Dev Team has released a tool for OSX named Absinthe, with Windows and Linux versions set to follow soon. The iPhone Dev Team have announced a command-line based tool which is expected to be available to download shortly.
It's worth noting that there is always some level of risk involved when jailbreaking a device. If you understand the dangers and still want to go ahead, you can find the download in the source link below.
Update: The iPhone Dev Team has updated its most recent post with some help for users having trouble with the Absinthe tool.