So you say you have an iPhone 3GS along with that jailbreak itch? Hit the link and get your download on. As always proceed at your own risk. TiPb and all of it's staff take zero responsibility to any wrong doings that may occur while using the software.
OH (original hacker, yo!) George Hotz has posted the RC2 version of his iPhone 3GS jailbreak tool, purplera1n. Along with other improvements, the new version supports Vista, Windows 7, and supports 64-bit.
If any of the above interests you, and you're a responsible adult who understands the risks involved, hit the link below and check it out. Jarrrr!