I made a quick tour over at Motorolas website, and what I saw was discouraging, atleast when it comes to make a DSP plugin for this board.
The DSPs I looked at were mostly in 200 pin surface mount packages. That alone makes it a lot of work, and something most ppl wouldn't fancy fitting themselves. They are mostly 3.3Volt or lower voltage devices aswell, working with 3.3 volt I/O.
But they are very cheap, and it is a pity it's not viable on this board.