Beginning today, Apple is offering owners of 550MHz or 667Mhz PowerBook G4s the opportunity to upgrade their CD-RW or DVD-ROM drive to a CD-RW/DVD-ROM combo drive for US$299. Orders can be placed in the U.S. or Canada by calling 1-800-919-2775 and entering access code 72523. Apple will send a box that can be used to send the PowerBook G4 to an Apple Repair Center to complete the upgrade. Orders can also be placed at Apple retail stores and Apple Specialists in the U.S. and Canada; additional options are available for Latin America, Europe and the Asia Pacific region. The offer ends April 30.