CyanogenMod is one of the most popular custom ROMs for Android phones, offering users a replacement for the default firmware that comes with a number of phones. The first release candidate of CyanogenMod 6.1 has just been released, and it includes a number of performance enhancements as well as features that may not be available with your phone’s stock software, including FM Radio support for phones including the HTC Google Nexus One, Bravo, or Supersonic.
CyanogenMod 6.1 RC is based on Google Android 2.2.1 and among other updates, includes bug fixes, status bar themes, kernel optimizations, touch-to-focus support for the camcorder, quiet hours for notifications, a file manager, dual-mode snoozing, and the ability to compose SMS by long-pressing the search button. There’s also support for sound recording and Bluetooth OBEX enhancements.
You can find a complete list of changes at the github page, and more information and download links and installation instructions for supported devices at the CyanogenMod web site.