any good development-oriented includable .mk files out there?

[Robert P. J. Day]

  ok, let me ask that again in english.  i have several C and
shell-based projects, on top of which i've written numerous .mk files
for inclusion to do things like take a bunch of sources and create,
say, a shared library out of them.

  for instance, in a directory full of sources, i might have a single
Makefile which contains, among other things:

        ...
        SRCS = foo.c bar.c fubar.c
        include sharedlib.mk

at which point "sharedlib.mk" will kick in and, naturally, use
whatever is in ${SRCS} to build a shared library.

  i've written most of those myself and they seem to work fairly well,
but i'm wondering if there's a standard set of makefiles like this
somewhere.

  thanks.

rday