X-Gold 608 Unlock

Currently, the 3G (software) unlock which is not baseband-dependent is the biggest missing piece of the iPhone community. It is more difficult than the previous unlocks due to the fact that the baseband bootloader is signature checked. The Dev team has successfully unlocked all baseband versions until 02.11.07, by a baseband exploit. The unlock is planned to be released in New Years Eve before 2009 (31.12.08). 

Class 1

 * Find an exploit in the bootrom to break the chain of trust
 * Improve by several orders of magnitude the NCK brute forcer, and find a way to extract the CHIPID and NORID
 * Find the theorized algorithm of NCK generation

Class 2

 * Use a SIM hack such as the TurboSIM Unlock
 * Find a way to patch running memory to "unlock" the phone on every bootup

Resources

 * Read about the X-Gold 608
 * Read geohot's blog post