Everyone loves GNU Make. Well, that's not true - but now that I've delved into it I've come to appreciate it for building things via the command line without that fancy IDE stuff. However, I've become frustrated with the prevalance of the famous WinAVR "mfile" makefile template. The template is good, but copy-pasting it all over the place feels like re-inventing the wheel, and there's features missing I found myself patching in over-and-over.
While developing my LUFA USB Stack I developed a new modular set of GNU Make makefiles, to give a re-usable set of functionality to the large number of included projects. This build system allowed me to add in or fix functionality in the one place, and have the changes automatically propagate out to all the dependent projects.
As LUFA has a few specific requirements that made the build systems not quite usable generically as-is, I decided to adapt them into a new project, "Dean's Makefile Build System" (DMBS). To try to encourage its adoption, I've made it public domain for all to use. It has a high-emphasis on giving human-readable error messages for common failures that generally result in obscure hard-to-debug output messages in other makefiles.