The amazing Geohot has recently released his purplera1n iPhone 3Gs jailbreak! Check it out on his blog, or head straight to the website to grab your own copy.
Anyway, I had the privilege of working with him and westbaer (and the rest of the chronic dev team) on the Mac version of purplera1n, which we released a few hours ago. It works very well, and requires no interaction with the iPhone at all! Even better, you can use the iPhone Dev Team’s ultrasn0w for an iPhone 3Gs unlock!
So, enjoy your jailbreak, and if you appreciated my work on the Mac version, feel free to donate!