1991. MorphiCL
      MorphiCL is a (possibly misguided) attempt at creating a GUI for CL loosely based on Squeak/Self Morphic
1992. Movitz
      Movitz is a Common Lisp implementation that targets the x86 PC architecture "on-the-metal"
1993. MPC
      MPC is a fork of Drew Crampsie's Smug, a monadic parser combinators library for Common Lisp
1994. MPD4CL
      MPD4CL is a library to write Music Player Daemon client programs
1995. MSL-Test
      MSL-Test (test.lisp) is Paul Foley's Test Framework
1996. MT19937
      MT19937 is a portable Mersenne Twister random number generator
1997. multiple-value-variants
      multiple-value-variants gives access to multiple-value variants of operators through one macro: multiple-value
1998. multisets
      Library of set operations on multisets
1999. Music
      Free software related to creating or manipulating music in Common Lisp
2000. Music Mind Machine
      The Music Mind Machine research group at the Universities of Nijmegen and Amsterdam have a variety of Common Lisp software available for the computational modeling of Music cognition including:

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