Windows Media Player uses time compression, I'm told, to allow playback of MP3's at speeds up to 2x normal with automatic pitch correction to remove the chipmonk effect.  The result is the gold standard in my book for playback quality for fast audio.  Unfortunately, it's not very portable.  Interest in the concept and making it portable seems widespread, but "thin".  So, my tiny iRiver T-10 MP3 player can speed up files, but doesn't provide any pitch correction.  The result at the fastest speed isn't generally useable.  Organizations that help the visually handicapped offer tabletop and bulky portable playback equipment for tapes and CD's  that can do this for moderately high prices.  Fifteen years ago portable cassette tape players were available, though difficult to locate, that played at 2x speeds, had manual pitch correction control and sold for $50, about what the iRiverT-10 sells for today.  Some 10 years ago Brigham Young University investigated the use of the same concept with video tapes of lectures for students, but nothing further came from the work.  With the need for increased productivity and faster life styles, plus  growing availability of portable video and audio players, it's suprising that audio book sellers, educational institutions, such professional organizations as the AMA, military trainers, and corporations with training programs haven't pursued 'speed listening' and viewing.  Fortunately as computers  using the Windows Media Player become smaller, cheaper and more portable this speed listening and viewing option will be more available for the retired community, during exercise, for workers in the field, commuters and visually handicapped.