iTour-Pop Portable Rechargeable Speaker for iPod, Sansa, Zune, iPhone 5, 4S, 4, 3GS, 3G, BlackBerry, HTC EVO, DROID, Samsung Galaxy S3, 2, LG Optimus G, and more (Color Option: Black)
I am no audiophile, but I am very happy with this little speaker.  For such a small device, and such a reasonable price, it provides a big, clear sound, much better than the old speakers I had from creative.  Definitely use it in the pop-up mode - it makes a huge difference.