If you like to bring along your own pillow when travelling, even during airplane trips, go for the Sound Oasis hypoallergenic polyester fiberfill pillow. It has two ultra-thin stereo speakers positioned deep within the foam.
A 73-inch-long cord with a standard 3.5 mm headphone plug can link the speakers to your smartphone, laptop or MP3 player for playing your own recorded soothing music or any of dozens of free sleep-sound apps available for iOS and Android devices or via websites.