Reuse

CodeWeb: Data Mining Software Development Experience in Open Source Code
A GPL'ed tool for data mining library usage patterns in existing applications. Can be used to guide and check usage of a software library much like a tutorial. Future work includes data mining other kinds of development experience such as evolution and porting experience.
http://codeweb.sourceforge.net/

Composable Software Systems
We develop new models, theories, methods, languages, and tools for classifying, specifying, analyzing, and designing software systems beyond the component level. This support could lead to substantial reduction in maintenance costs, improvement in software resuse, and increase in quality of software.
http://www.cs.cmu.edu/afs/cs/project/compose/www/index.html

Prosperity Heights Software
Offers consulting, training, and information on domain-specific engineering, reuse-driven process improvement, and adaptable components for software product line reuse.
http://www.domain-specific.com/

The Reuse RKT
Search and browse listings for more than 3000 open source applications, libraries, and functions. Includes links to C and Unix programmer's FAQs and other references. Man pages link directly to source code.
http://www.rocketaware.com/orbit/Lo/

Venari Project
The thrust of the Venari project at Carnegie Mellon University is addressing the problem of search, hence the name. We touch upon areas in programming and specification language design, semantics, and implementation; concurrent and distributed systems; databases and persistent objects; and software development libraries and environments.
http://www.cs.cmu.edu/afs/cs/project/venari/www/home.html