It isn't cheap, but the Bose SoundLink Mini is an excellent-sounding Bluetooth speaker that is especially useful for those who travel frequently.
Bose SoundLink Mini Review
Bose SoundLink Flex review: A Bluetooth speaker with striking looks, pleasing sonics
Bose SoundLink Mini Review
Bose SoundLink Mini Bluetooth Speaker Review
Bose SoundLink Mini II Review
Bose SoundLink Mini review
Bose SoundLink Mini II Bluetooth Speaker Review - LiquidAudio
Bose SoundLink Mini II review: A great Bluetooth speaker gets even better - CNET
Bose SoundLink Mini II review: A great Bluetooth speaker gets even better - CNET
Bose SoundLink Mini review
Bose SoundLink Mini review