The SIDstick is a pocket-sized chiptunes player featuring:
* Removable Storage supporting microSD cards, 1 card can hold 20,000 songs
* 20+ hour battery life
* Super Hi-Quality hardware-based playback at 31kHz sample rate, >16 bit resolution
* Completely Open, hardware and software are available under the MIT license
* Upgradable with connections on the board

Here are the details of SIDcog, the core audio processor;
* 31kHz sample rate
* >16bit resolution
* Full filter support – any combination of Lowpass, Bandpass and Highpass filter
* Full envelope support with a logarithmic release/decay curve. ( uses the same logarithmic approximation as a real SID)
* Supports all 4 waveform types
* 16 steps main volume
* Waveform reset bit works. (many Rob Hubbard tunes relies on this exact behaviour)
* Ring modulation
* Oscillator synchronization

Get The SIDstick!.

Too bad its emulated.. but looks fun.

(thanks burnkit2600!)