One of my best friends sold me an Android HTC T-mobile G2. Him told me that an smartphone can change the lifestyle, that was right for me too!
After 2 months of playing with it, and being tired of using closed source software in an open source operating system (a.k.a Android), started to look for free (as in bear and as in speech) alternatives. Be warned that you will void your device warranty and should backup all your personal data: phone contacts, messages, etc, so you can recover it, after all, freedom needs some job ;)
UPDATE 2011-07-19: Following instructions also work with Ubuntu 11.04 Natty Narwhal.
Programming for mobile in Linux was a pain in the neck 6 years ago and it is still a pain in 2011. The following articles may help you in your journey:
If you survive let me know :)