Jam Plus Wireless Speaker ($60) is one of HMDX's newest products. Building on the general design of its original Jam, this new model is noteworthy in that it allows you to pair up with a second unit for stereo audio output. The battery inside isn't huge -- it only provides four hours of playback -- but it's not totally crazy for the price. Jam Plus comes in a number of bright colors, and each has physical controls on the front, plus power and aux…
