Quick Take: Griffin's SmartShare ($15) splits the audio headphone/line-out jack of any audio device into two separate ports, allowing for two sets of headphones and two users to listen to the same device. Although this concept is nothing new, Griffin takes it a step further and integrates volume control into each jack. This is a very welcome feature, since different headphones tend to have different volume outputs. With the SmartShare, friends can each boost the volume to their liking. It should be noted that although there are direct volume controls on the splitter, they're not designed for sole control--you can't turn the volume all the way down to mute or past the device's output level using the in-line dial.