The FOSS4Lib database is a new(ish) site for finding open source software in libraries.
The FOSS4LIB resource site for open source software in libraries was created with funding from The Andrew W. Mellon Foundation by LYRASIS Technology Services to help libraries decide if and which open source software is right for them in service to their patrons. Consultants specializing in library open source software created the FOSS4LIB self-guided readiness assessments to help libraries determine if open source software is right for them. The site also features a registry of software packages to help libraries find information about open source software service providers, events, and usage by peers.
One of the newest features of the site is the ability to add your library (institution) and list what open source you’re using. I think that while a directory of open source software is useful in and of itself, a directory that tells you what libraries are using the software is even better! If your library is using open source you should certainly register and add your library and the software you’re using.