2081. OpenMusic
      OpenMusic is a visual programming language based on Common Lisp and CLOS
2082. ops5
      OPS5 is a rule-based or production system computer language, notable as the first such language to be used in a successful expert system [...].
2083. opticl
      An image processing library for Common Lisp
2084. optima
      [deprecated by trivia, see link below] A pattern matching library
2085. Option-9
      A shoot-'em-up game written in Common Lisp
2086. optparser
      optparser is a Unix command-line options parser for simple shell scripts, geared towards ease-of-use and unambiguity
2087. orcabot
      A full-featured IRC bot in Common Lisp
2088. ORF
      A macro seen in some utility/convenience layers
2089. org-davep-cldict
      org-davep-cldict is a Common Lisp Application that provides a McCLIM based interface for talking to a dict server
2090. org-davep-dict
      org-davep-dict is a Common Lisp networking protocol library for talking to a dict server

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