I've dug out all the original (i.e. non forking ports) gnuboy source code I could fine and made them available via svn. This includes the unreleased 1.0.4 code that fixes compatibility for a few games. I've tidied it up and made a 1.0.5 version that works under Windows and (x86) Linux and SDL, it should run fine on all the other platforms too, like MSDOS :-)
The project page is http://code.google.com/p/gnuboy/
Some of the under the covers features of 1.0.5 is easier porting. Using the same code that the Windows release has I've made an initial proof of concept build for Dingoo native OS http://code.google.com/p/gnuboy/downloads/
so you can try it out on your device.
More information about the Dingoo version is at http://code.google.com/p/gnuboy/wiki/DingooPort
(and check out the rest of the wiki).
It runs, performance isn't quite full speed and sound is "icky". I'm not yet sure what the performance is as I've not got an fps indicator going yet :-)
I'm hoping to do some more playing with this on Sunday, not sure when the next visible milestone will be but I thought I'd share what I have so far (and in case anyone wants to join in). Part of the project may involve ways of improving the SDK we have (e.g. memcpy performance along with some of the file stdio file functions).
Thanks to Joyrider and SiENcE for sharing their code, I used (a modified version of) Joyrider's approach to RTC saves. Almost everything else is currently plain old gnuboy code.