A compiler made only from PEG-based transformations for all stages

Anything by Ian Piumarta is worth reading, and this is no exception. http://piumarta.com/

Also, for those interested in minimalism, VPRI has a project to recreate the entire computing world with 20k lines of source (logic, os, compilers, gui, etc.) They're doing a very interesting and very swell job so far. This appears to be related to that project.