A new jailbreak has been released a few hours ago, it is called Limera1n and unfortunately it’s only available for Windows at the moment.
We take no responsibility for using jailbreak, make sure you are aware of the risks involved.
The Limera1n Jailbreak is available for the following devices: iPhone 3GS, iPod Touch 3G, iPad, iPhone 4, iPod Touch 4G but it won’t work with newer iPhone 3GS models with a different bootroom.
Just go to limera1n’s website and follow the instructions.
You can also read the Arabic guide by iPhone Dev Team Arabic.
Arabic version of this post on SaudiMac Arabic Edition.