NUC (Next Unit of Computing) makes my Mac Mini look big.
I still like the audio output stage on the Raspberry Pi; but another motherboard that comes to market in August is the
Beagleboard AX-15:
Open source hardware (that's important). Official Specs:
- Dual-core Sitara AM5728 ARM Cortex A15 @ 1.5Ghz
- 750-MHz C66x DSP for analytics
- Quad-core PRU for real-time control
- Dual-core Cortex-M4 for even more real-time control
- 4GB eMMC
- 157 general purpose input/output (GPIO)
- 20-pin ARM JTAG
- eSATA
- HDMI
- 2 1Gb ethernet ports
- 2GB DDR3L
- µSD card slot
- Micro USB 2.0 slave
- 3 ports on a USB3.0 host
- Audio in and out jacks
http://makezine.com/2015/10/14/beagleboard-officially-reveals-the-x15-and-its-a-beast/
Here's hoping the vacuum tube output stage on brass hex standoffs is available for it.