HO-CVS is a version control system based on MetaCVS. In addition to the features of MetaCVS, it features module level versioning, the ability to reference every version (since there is a tag after every commit, which is extremely useful but slow), complex versions like #v1.2.3 designed to carry information about the change, operation hooks, and a somewhat powerful log command.
CLSQL is an SQL database interface for Common Lisp. It provides object-oriented and functional access methods to the underlying database, which can be one of MySQL, ODBC, PostgreSQL, or SQLite. It uses the Unified Foreign Function Interface (UFFI) and thus supports the CMU Common Lisp, Steel Bank Common Lisp, and Allegro Common Lisp implementations.
ACL2 is a mathematical logic, programming language, and mechanical theorem prover based on the applicative subset of Common Lisp. It is an "industrial-strength" version of the NQTHM or Boyer/Moore theorem prover, and has been used for the formal verification of commercial microprocessors, the Java Virtual Machine, interesting algorithms, and so forth.