It's pretty easy to put small wave fragments embedded into your programs to play them back. But, playing loops and things greater than 16Ksamples, they won't fit into on-chip SRAM, so you will have to use DMA to play them out of off-chip memory. A good trick would be to store the samples in the Flash chip.
a project has been started to play samples out of the flash memory, however, there are still many bugs left to work out! In the meantime, you could take up the development yourself if you want, by clicking here.
You better believe it! Check out EZ-Kit Lite MIDI Interface
Yes, go for it!