Dependent ML: DML
   Conservative ML extension, has type system to enrich ML with restricted form of dependent types, to allow many interesting program properties: memory safety, termination can be captured in type system and thus be verified while compiling. Description, cod
   http://www.cs.bu.edu/~hwxi/DML/DML.html

Extended ML
   EML is a framework for specification and formal development of Standard ML programs. Description, publications, tool support, education resources.
   http://homepages.inf.ed.ac.uk/dts/eml/

ML Kit
   Standard ML compiler.
   http://www.it-c.dk/research/mlkit/

MLRISC
   Framework for customizable, retargetable and optimizing compiler back ends, written in Standard ML. Successfully retargeted to many architectures. Deals elegantly with special requirements imposed by execution model of different high-level, typed language
   http://cs1.cs.nyu.edu/leunga/www/MLRISC/Doc/html/

MLton
   Whole program optimizing compiler for Standard ML.
   http://www.mlton.org/

MetaML
   Metaprogramming ML, needs SML first; part of OGI Mustang Project for Staged Programming. Pacific Software Research Center; download, install instructions, links.
   http://www.cse.ogi.edu/pacsoft/projects/metaml/

Moscow ML
   ML system for DOS, Linux, Windows.
   http://www.dina.kvl.dk/~sestoft/mosml.html

Open Source Release of MLj
   SML to Java bytecode compiler, based on Persimmon's MLj.
   http://www.dcs.ed.ac.uk/home/mlj/

Poly/ML
   Standard ML full implementation: compiler and environment, has libraries for MS Windows, X Window. [Open Source]
   http://www.polyml.org/

Standard ML of New Jersey
   SML/NJ is a compiler and programming environment for SML, with associated libraries, tools, documents. Descriptions, news, downloads (Unix, Windows), literature lists, FAQs, links, contacts. [Open Source, Lucent]
   http://www.smlnj.org/

TILT
   TIL-Two compiler; goal: make compiler for ML-family languages (SML'97, Caml Special Light, KML) that uses types throughout compiling to emit better code without losing safety or correctness; joint effort with Carnegie Mellon. Descriptions, papers, people,
   http://www.cs.cornell.edu/info/people/jgm/tilt.html

TILT Compiler
   Self-checking Standard ML compiler, uses Typed Intermediate Languages; while compiling, types are translated with code, type-checking occurs to check compile results; funded by NSF. Descriptions, license, mail list, downloads, links. Carnegie Mellon.
   http://www.tilt.cs.cmu.edu/

The Alcool-90 Experiment
   Experimental ML extension with run-time overloading and type-based notion of modules, functors and inheritance. Large HTML text document.
   http://pauillac.inria.fr/~rouaix/papers/AlcoolExperiment/plan.html