Generating dependency information with GCC

Something I would have like to know long ago: GCC's -M flag generates a piece of text with the dependencies that you can copy-paste into your Makefile:

boink@donatello$ gcc -M parrot.c
parrot.o: parrot.c /usr/include/ctype.h /usr/include/_ansi.h \
  /usr/include/newlib.h /usr/include/sys/config.h \
  /usr/include/machine/ieeefp.h /usr/include/cygwin/config.h \
  /usr/include/stdio.h \
  /usr/lib/gcc-lib/i686-pc-cygwin/3.3.1/include/stddef.h \
  /usr/lib/gcc-lib/i686-pc-cygwin/3.3.1/include/stdarg.h \
  /usr/include/sys/reent.h /usr/include/sys/_types.h \
  /usr/include/sys/types.h /usr/include/machine/types.h \
  /usr/include/sys/features.h /usr/include/cygwin/types.h \
  /usr/include/sys/sysmacros.h /usr/include/stdint.h \
  /usr/include/sys/stdio.h /usr/include/string.h