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.
otl is a text processor for generating markup from readable lightweight markup. Much of both the input and output formats can be customized. HTML output is bundled as an example. otl supports complex structures such as nested ordered and unordered lists, headers and footers, and tables.
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.
Avsomat is a variable star astronomy framework. It supports the automating of observation scheduling, identification and photometry of variable stars on CCD images, reporting, management, and verification of results. It uses electronic charts of the variable star fields and maintains a view of the current results in the form of a collection of interlinked Web pages with feedback forms, allowing members of the observer community to participate in locating errors.