If you're not rocking an iPhone 4, or the third or fourth gen iPod touch, and instead have a iPhone 3G or 3GS, or a first or second iPod touch in your pocket then, for once, you can get one over on your early adopting fanboy buddies.
For the The Dev-Team has noted that iOS 4.2.1 jailbreak for these older devices (running on the older bootrom) is already ready for your device.
This is due to the latest RedSn0w build, 0.9.6b3, that hit the web-waves last week in order to hack the GM build of the latest iOS.
“Due to a combination of our original pwnage2 exploit, the arm7_go exploit, 24kpwn, and limera1n, your device is just as jailbreakable as ever”, read a statement on The Dev-Team's website. “You reap the full benefit of an untethered 4.2.1 jailbreak”.
Newer devices are likely to see an untethered jailbreak (so you don't need to hook it up to your PC every time it runs out of battery to reset) in the near future, with @comex currently working on it.
Now, as always, we warn you that jailbreaking your iDevice takes some knowledge of its inner workings so as you don't mess it up.
And whilst the practice is legal, don't expect the Geniuses to be overly helpful if you take a troublesome jailbroken device into the Apple Store.