TheRealMafoo on 17 October 2009
The best tools are redsn0w and ultrasn0w. Redsn0w is just for jail breaking your phone so you can run more apps on it. Ultrasn0w is for hacking the modem to use on other carriers (T-Mobile usually in the US)
Here are the links.
http://blog.iphone-dev.org/post/126908912/redsn0w-in-june
I think if you have the latest firmware, and have the latest OS, you might be SOL at the moment. Not sure. I have not read these in a while, but I thought part of iPhone OS 3.1 was geared to stop this sort of thing.
