To my knowledge this was the original iPhone jailbreak (JailbreakMe). I was on IRC whilst the author was seeking donations before releasing it ;) Ran it on my trusty iPod Touch 1g only minutes after it was released.
This was for iOS 1.1 though, not iOS 1.0, as it was not encrypted and was never really locked down. It was Apple's choice to release iOS 1.0 without the security enabled that made further jailbreaking efforts much more straight-forward, because there was extensive knowledge of the file system.
This was all well before there was an App Store, and when Apple's public position was that they'd never allow third-party software on their platform ;)
