Errr, not really. Whilst we paid about $50 per cpu at the time due to shortages, the SA1110 CPU is sub $25. Even if you use a plain MP3 decoder (and as such sacrifice playing WAVs, OGGs, WMA, etc) you still need a decent CPU to do the rest of the stuff - playlist management, etc.

It's much more cost effective to just use a fast general purpose CPU. You'll notice that the iPod, Riot, empeg, Nomad, etc all use a general purpose CPU (or slight DSP spin in the case of the nomad 3, I believe) to run the HDD player software *and* do the audio decoding. This is for a good reason - trying to do it with less ends up in products like the Neo; yes, they play mp3s from a hard disk, but they're not very convincing.

Hugo