Audioengine just released a new DAC, or digital to analog converter, that significantly improves the quality of the audio from your Mac or PC. The D3 is a 24-bit DAC that connects via USB and doesn't require any special software. Just plug it in, then connect your headphones or external speakers for better sounding music. The D3 shows up just like any other audio output, can be controlled through your computers system volume settings, and is built into an injection molded aluminum case so its durable enough for travel, plus it doesn't need an external power source so there aren't any extra cables to get in your way. It's priced at US$189 and available at the Audioengine website as well as other retailers.
Check It Out: Audioengine Brings 24-bit Digital Audio Quality to Your Mac