Portable MP3 player with digital out?

I'm finally getting ready to join the whole portable world, and am interested in buying a harddrive based mp3 player that I can also hook up to the optical input on my Maven receiver to take advantage of its built in DAC thus bypassing the (most likely kinda crappy) DAC on the player itself.

I know the ipod is out, what should I consider?

Cheers,

-Andrew