For those of you who like to 'stick it to the man' by jailbreaking your iOS devices, you'll be pleased to know that the good folks at the Chronic Dev Team have released a shiny new tool for all your jailbreaking needs. Better yet, it's an untethered jailbreak, meaning that it should 'just work' without requiring any special boot-time tricks. The application can jailbreak any device at iOS 4.2.1 without trouble. If you're interested, throw on your tye-dye shirt, blast your Pearl Jam, and head over to the GreenPois0n website to mash 'GO' on that download button.
Not sure about all this 'jailbreaking' business? Here's a quick overview for anyone who'd like one. Essentially, the process of jailbreaking allows root access to the device, meaning that it is possible to run code not approved by Apple. This means that a whole slew of new apps, tweaks, and customizations can be made - many of which would not normally be allowable on the App Store (such as emulators, for example). It is completely legal (in the US - check the laws in your country) to jailbreak your device, but do note that some corporations frown upon employees who jailbreak a company phone. Also, this shouldn't even need to be said, but iPhone Life does not condone piracy of any sort - please don't do anything illegal with your phone, jailbroken or otherwise.