Unlocking your mobile.

[Grizzly]

Firstly saying that it is illeagal to unlock your phone is a myth!
You can at invalidate your warranty with some suppliers.
But if say you have upgraded to a newer model.
The old one is then yours to do with as you wish, well at least in the U.K.

Check out giffgaff unlockipedia!
http://giffgaff.com/unlock

Enjoy!
Grizzly