When you get tired of carrying your iPod, you might try plugging it into this self-propelled contraption. It's from Japanese robot venture ZMP, which calls the device Miuro, short for "music innovation based on utility robot technology." The Miuro comes with four built-in speakers (ZMP has partnered with audio company Kenwood) and, like many of us, dances along to the music. It moves either automatically or via remote control, and can understand a map of a room. ZMP plans to begin selling the Miuro by the end of the year, priced at 108,800 yen, or a little over $900.