GNU Automake  
   Freeware - Generates makefile.in files from makefile.am input files, as part of the official GNU coding standards and build process. Requires GNU autoconf.
   http://www.gnu.org/software/automake

Imake  
   Freeware - Generates traditional makefiles by using the CPP preprocessor and makedepend programs to assemble makefiles from templates and Imakefile control files. From the MIT X11 project.
   http://www.kitebird.com/imake-book/

Makedep  
   Freeware - A dependency generator that analyzes C/C++ source code and generates a dependency file for inclusion into traditional makefiles.
   http://sourceforge.net/projects/makedep

Makeit  
   Freeware - Generates GNU Makefiles for C/C++ projects, featuring dependency scanning and variant compilation support. Part of the OSE application development framework.
   http://ose.sourceforge.net

CMake  
   Freeware - Generates traditional Unix/Windows makefiles for C/C++ projects from manually created input files written in the CMake language.
   http://www.cmake.org/HTML/Index.html

Bakefile  
   Freeware - Generates traditional makefiles from a compiler-independent build tasks. Features output of Makefile.in files for autoconf, makefiles for vcc/bcc compilers, and use on wxWindows new build system.
   http://bakefile.sourceforge.net/

Makedepend  
   Freeware - A dependency generator for C/C++ code used by Imake from the X11 distribution. Can be used without Imake to generate makefile dependency files.
   http://www.snake.net/software/imake-stuff/

Smart Makefile Now  
   Codefast - Smart makefile, perlfile, and antfile generators for software processes, including software builds. Features collections, dependency scanning, a knowledge base, makefiles for parallel builds, multiple platforms.
   http://www.codefast.com