Here's a funny binary of the cleaned & stripped core + GUI version.

http://spacy51.sp.funpic.de/VBA-M/VBAMin.7z
Not using assembler, so it might be slower. Also a lot of features removed. Just use it if you are curious. Has automatic save detection though. Save states not compatible anymore. Save states will not be comaptible with anything, only battery files. Screen capturing&recordning might not work anymore.

Source code here: http://code.google.com/p/gbxemu/source/checkout

Next step will be rewriting the core to a clean C++ class in a static or dynamic library. After that is finished & working correctly, features will be readded in a clean manner. Don't expect any binaries soon.

You did what I always wanted to happen.

Holy fuck This is great, really, more than great. Forgotten should have done this ages ago!

Up until recently, I had the feeling whenever I removed something, people were angry to see features go away, so that's probably why Forgotten never managed to improve the code quality.

Nice work Spacy ! Way to go !

If you're interested, I started a similar project a few months ago. It's more Linux oriented (ie only the GTK port remains), but has a few nice cleanups / rewrites in the core. The goal was to write a clean GBA emulation core, but I got stopped due to the lack of time. Maybe you'll be able to use some of the code I have written.
I may have a more recent version with a rewritten MMU floating around, in case you'd want to see it.

http://github.com/bgK/vba-ttb

Oh, nice!

I am especially interested on changes in the GBA core.

What VBA-M SVn version was this based on, so I can make use of diff tools to track your changes?
Judgung from the date you created that git thing, it might be around SVN854

Yes, I forked the vba-m source code at r854. I did a rebase a few minutes ago to pick up the changes up to r905, but those were mostly MFC related anyway.

Among things that may be useful is the thumb core, cleaned up using templates instead of macros. I was too lazy to do the same to the arm core.
I did a few clean ups in the graphics area, but a lot remains to do.
I also did some changes in to the cartridge saves, but you probably won't like the removed savegame autodetection.