Cycling with headphones on can be a tad dangerous, good thing someone invented the CyFi. It’s basically a wireless speaker that can mount to your bike and allows for the transfer of “audio from your cell phone, PDA, or MP3 player via Bluetooth (A2DP)” from up to 30 feet away. It’s slightly larger “than a deck of cards and weighs 4 ounces.”

Source: Gear Patrol