MuscleNerd is recommending that this tool NOT be used as it contains copyright Apple code. [via iDB]
Unfortunately they achieve this by directly embedding Apple code in their program (15 times!). That's the kind of copyright infringement we stay away from. Hosting this app can lead to DMCA takedowns, etc. (Anyhow, redsn0w doesn't need the IPSW for each tethered boot either..it fetches the images from Apple's servers once and then caches them.)
PwnDevTeam has released a beta of Ac1dSn0w, a new utility to jailbreak the iPhone 4, iPhone 3GS, iPad 1, and iPod touch 4G on iOS 5.
I'm pleased to announce that we've just released Beta 1 of Ac1dSn0w for Mac OS X Lion (should also work on Snow Leopard). Ac1dSn0w allows you to jailbreak your iDevice tethered. It also provides features like Tethered Boot, Pwned DFU, and Exit Recovery to get your device out of Recovery Loop.
Supported Devices (iOS5/iOS5.0.1):
iPod Touch 4 G
The team has posted the following steps to using their new utility.
1. Download Ac1dSn0w from [Here] [Mirror]
2. After downloading, open it and you'll see the following screen:
Note: You can click 'Show Console' to see some device related information. It also shows you the current state of your jailbreaking process. The Assistant Panel helps you to put your device into DFU Mode.
3. Connect your device with your Mac.
4. Turn your device off.
5. Click 'Show Assistant' and follow the onscreen instructions to enter DFU Mode.
6 . Once you're in DFU Mode just hit the 'Jailbreak' Button and wait until it's done (the device will reboot).
7. Put your device again into DFU Mode (Step 5) and hit the 'Tethered Boot' Button.
Done: Your device should now be jailbroken with Cydia installed.
Hit the link below to learn more about the utility.