A-A-P
   Open Source - A-A-P is an experimental make tool. Features include a special AAP makefile syntax, automated dependency support for Unix C programs, and a GUI interface written in Python.
   http://www.a-a-p.org/

Boost Build
   Freeware - A Make replacement with a simple and high-level target language. It supports build variants, and several different compilers and tools.
   http://boost.sourceforge.net/boost-build2/

Build
   Open Source - A software build system implemented on top of GNU make featuring position-independent non-recursive multi-makefile include-based structure, complete inter-project dependency tracking, and extensible translator framework.
   http://kolpackov.net/projects/build/

Cons
   Freeware - A make replacement written in Perl featuring MD5 file content and build signatures, dependency scanning, viewpathing for source and derived files, multidirectory builds, and Perl build actions.
   http://www.dsmit.com/cons

Cook
   Freeware - A make replacement featuring file fingerprints, dependency scanning, viewpathing, parallel threads, distributed rsh builds, cross compiling, and build actions in the "cook" description language.
   http://miller.emu.id.au/pmiller/software/cook/

ElectricAccelerator
   Electric Cloud - A make replacement that distributes builds across multiple cluster machines for faster builds. Features automatic code dependency detection (and correction in some cases), and plug-compatibility with GNU Make and Nmake.
   http://www.electric-cloud.com

GNU Make
   Freeware - A make program featuring pattern-matched viewpaths, parallel threads, multiple platforms, conditional directives, makefile regeneration, and an advanced Make description language.
   http://www.gnu.org/software/make/make.html

Jam
   Freeware - A make replacement featuring dependency scanning, per-target viewpathing, parallel threads, multiple platforms, variant builds, and control flow statements in the Jam description language.
   http://www.perforce.com/perforce/loadsupp.html

Jmk
   Freeware - A make program written in Java, featuring a traditional make description language and shell command target actions.
   http://sourceforge.net/projects/jmk

KJam
   A make replacement based on Jam, with more powerful features than the original Jam. Features dependency scanning, per-target viewpathing, and control flow. Distributes builds across multiple cluster machines for faster builds.
   http://www.oroboro.com/kjam/docserv.php

MPI GNU Make
   Chambeau - A modified GNU make that uses the MPI Message Passing Interface for excellent scalability on multiple machines. Authors now say use 'GNU Make -j' instead.
   http://www.llnl.gov/icc/lc/DEG/pmake/pmake.html

NAnt
   Freeware - Not Ant is like Ant, but uses C# and .NET technologies.
   http://nant.sourceforge.net/

Nmake
   Lucent - Features dependency scanning, viewpaths, parallel and distributed rsh execution, a coshell, compiled makefiles, C preprocessor, variable editing, and a powerful Make rule language.
   http://www.bell-labs.com/project/nmake

Odin
   Freeware - A make replacement featuring dependency scanning, viewpaths, distributed rsh execution, cached derived files, variant builds, conditional directives, and an Odin rule language.
   ftp://ftp.cs.colorado.edu/pub/distribs/odin

Opus Make
   Opus - A multiplatform make featuring dependency scanning, suffix-specific viewpaths, extended command and macro modifiers, CPP preprocessor directives, and iterators in the Make rule language.
   http://www.opussoftware.com

PBS
   Open Source - A Make replacement written in Perl featuring hierarchical builds, dependency graph node triggers, no built in rules, PBS/Perl syntax for PBSfiles, a Perl API for the system, and shell or Perl build actions.
   http://search.cpan.org/~nkh/

PVM GNU Make
   Freeware - A modified GNU make that uses the Oakridge PVM Parallel Virtual Machine to perform parallel distributed builds.
   http://sourceforge.net/projects/pvmgmake

SCons
   Freeware - A make replacement like Cons, written in Python and featuring MD5 file signatures, dependency scanning, parallel build threads, viewpathing, multidirectory builds, and Python build actions.
   http://www.scons.org

SMK
   Freeware - A make replacement, written in Python featuring global dependencies view, extensible dependency scanning, parallel build threads, multidirectory builds, automatic cleaning and extensibility via Python classes.
   http://home.gna.org/smk/

Sham
   Freeware - A tiny command-line prefix tool that can track dependencies for a file automatically without the need for a Makefile.
   http://sham.sourceforge.net/

Speedy Make
   Freeware - A very simple make replacement that uses an XML file (reminiscent of Ant) to specify files and actions to be executed on those files.
   http://www.speedymake.com

TrMake
   Open Source - A modular makefile system for multi-platform C++ development in Unix environment using GNU make 3.80 or higher, featuring modular makefiles and transparent handling of dependencies and sources of multiple projects.
   http://www.cs.bgu.ac.il/~orlovm/code/trmake/