Remember the Pipboy 3000 from Fallout? You can now build one yourself using a Raspberry Pi and an Adafruit 3.5″ PiTFT. The device has a 2200 mAh battery, 3D printed enclosure, and speaker with music from Fallout 4. The enclosure has cutouts for IO ports, so you can add additional items.
The complete list of parts and instructions are available on Adafruit.com.