I made a cool little project, a portable music streamer/player with a Raspberry Pi Zero W for my Chord Hugo or any usb dac (using RuneAudio). Stream music/radio stations, play local stored files, a diy poly for your usb dac. Runtime is up to 13h, i have used a 128gb micro sd card for local storage. Hardware cost 20 usd + microsd card + printing cost. It's a portable version of my Chord Mojo docking station, http://www.thingiverse.com/thing:1716990, a universal portable version with 18650 battery and standard mirco usb connector. Grab the files and instructions here: http://www.thingiverse.com/thing:2267531 A smaller/flat version for my Chord Mojo comming soon .