The legality of certain phone modifications in the United States, particularly those that allow phones to be used on wireless carriers for which they weren't originally intended, is currently on a congressional see-saw. Every three years, the Librarian of Congress has to approve or extend an exemption of the infamous Digital Millennium Copyright Act (DMCA) to allow or deny consumers the right to unlock (read: carrier unlock, and in some cases rooting/jailbreaking, but not unlocking bootloaders) their phones by circumventing digital rights management. Congress let the exemption slide earlier this year - read the gory details here.  Now a new bill has been entered that, if passed, would grant a permanent exemption to the DMCA for carrier unlocking, among other things.