I mean, I see a headline claiming a Brazilian company has unlocked the 3G iPhone, and that they are the first, but eBay is flooded with "unlocked" 3G iPhones. Are they really unlocked, or just full of BS?
The Brazilians are using TurboSIMs, if anything, but if it's a first-gen iPhone on eBay, it could very well be unlocked. If not, it's a simple process.
The 3Gs, unless they come from Hong Kong or Belgium, are not unlocked yet.
Some Australian/European carriers sell them unlocked for about $1000US, it's possible they got them from there. There is currently no software unlock for the 3G (the dev team said their unlock doesn't work on the 3G) and the Brazilian folks have a hardware unlock, TurboSIM.