In the last few weeks of demo coding, I have learned many things.
1. I rather dislike Blender as a 3D modeler, but it's about the least worst of my options. On the plus side, after messing with it for a few hours and reading copious amounts of documentation, I can now do cool extruded text things, in arbitrary Unicode fonts, provided I know where the OS hides them ;-) Of course, the exported text objects have tens of thousands of vertexes take up tons of disk space.
2. libminifmod can be built to suit your mod/xm/whatever, and only include code for the effects you need. I was scared for a minute or two when my effects weren't playing, but then I realized how to fix it.
3. On OS X, iPakk seems to beat UPX. Of course, it also cheats and takes advantage of Rosetta by generating a PPC binary (even if the source executable is i386). My last iPakk-ed build is actually 59k (but this is with temporary music, but without models or textures, so I'm pretty sure 64k will Right Out, as my current *one* model is 105k). UPX managed about 67k (for reference, the stripped, uncompressed executable is ~150k)
In other news, check out
RPM Challenge - it's like NaNoWriMo for music, and it's next month.