The Samsung BS300 Bluetooth speakers are compact, portable, and extremely versatile. If you're looking for a portable speaker that can be used with almost anything producing sound, this is one serious contender.
Source: Amazon.com is where mine came from. Around $130 the BS300 is pricey. It pays to shop around as BHPhotoVideo.com has them for $90. For comparison the Samsung P2 8gb media player can be found for $149. Yet for your money you get portable speakers that will work with any MP3 player, wireless speakers that will work with most cell phones supporting Bluetooth as well as every Bluetooth MP3 player I've tried including the Samsung P2, Samsung T10, Cowon S9, iriver SPINN, and Insignia Pilot. Using it with a cell phone it can serve as a hands-free speakerphone as it includes it's own microphone. It works great with my Samsung Instinct.
Dimensions: Much smaller than it appears in every add I've seen, the actual measurements are 95 x 47 x 13mm. Roughly 3.75" x 1.85" x .51". 62.6g weight. Small enough to fit easily in most pockets. You can see it here next to the Samsung T10 and P2. In the lower photo you can compare it's thickness to the Samsung T10.
Included: In addition to the speaker you get a USB charging cable, a 3.5mm to 3.5mm stereo patch cable, a small folding stand, a multi-language user manual, and a small (1 year) warranty card.
Connections: On the left end you'll find the DC charging port and a small connection point for a lanyard. On the right end you'll find the 3.5mm line-in port.
Controls: Most of the control are along the top edge. There you'll find the Power button, Play/Pause, Next/Prev, Vol+/-, a DNSe button and a small reset hole. On the front you'll see the microphone and above that a Call/End phone button. Above that are a charging status LED and an operation status LED.
Features: Although small, the BS300 packs in the features.
+ It's line-in jack lets you connect any electronic audio source directly.
+ On-board volume controls let you control volume from the speakers themselves.
+ The rechargeable battery lets you take it with you beyond the power grid, and means you'll never have to buy batteries for it.
+ DNSe settings include a 3D sound mode, a Bass Boost mode, and a combined 3D & Bass Boost mode.
+ As a speakerphone the BS300 allows Answering a call, Ending a call, Rejecting a call, Redialing, Voice Dialing, Switching a call between phone and speaker, and 3-way calling. Of course your phone has to support these features too.
+ You can have your phone and an MP3 player connected simultaneously to the BS300 and the music will pause when a call comes in.
Audio Quality: For such a small speaker, the sound is pretty impressive. You won't hear much if any bass from your music even with the DNSe bass boost on. At 1w per speaker (2w total) it's not going to shake the rafters, but is a very good alternative to earbuds when you need something extremely portable but also shareable. Sound is directional out the front, and drops off by nearly 1/2 from the back. The included stand holds the speaker up at an angle so you get the best audio it can produce. I've tested larger portable speakers that were worse, and none that were better. There is no appreciable stereo separation. The DNSe choices didn't seem to make much difference, with the Normal setting producing the best sound anyway. The Bluetooth feature allows volume control from the speakers OR from your player. Sound using the patch cable sounded only a little less tinny than using bluetooth, but will let you use any sound processing options your player has. The Samsung P2, for example, can use one of several DNSe (equalizer) presets over cable that won't work over bluetooth.
Summary: At $90 the YA-BS300 are a great value. More pocketable than any previous portable speakers I've found, they still do a great job of letting you hear the content of your media player without headphones. Don't lose the included charge cable though. The BS300s are rated for about 4 hours playtime, so expect to be charging them periodically. Those 4 hours should last you through a couple of movies. Battery life is my only complaint, as there is no way to swap in new batteries when your 4 hours are up. It'll take 3 hours or so to recharge the BS300. If you need a small hands free speakerphone for your cell phone, this is a fantastic choice. It wouldn't be hard to find a 12vdc to USB adapter so you could keep the BS300 charged in your car. I can't hear my cell phone's speaker very well. Using the BS300 makes call audio more easily understandable.