Cave Story, notorious Japanese early 2000s polished indie platformer now available for play on dreamcast? It seems so!
Here is a thread with some news and a link to a bootable CDI image.
http://dcemulation.org/phpBB/viewtopic. ... 4&t=102446
Here is the page for the project. i guess this is an interpreter for the already compiled game files, rather than a port of the (unavailable) source code.
http://sourceforge.net/p/nxdc/wiki/Home/