Xapian is a search engine library, scalable to collections containing hundreds of millions of documents. It's written in C++ with bindings for Perl, Python, PHP, Java, Tcl, C#, Ruby, and Lua. It is a highly adaptable toolkit that allows developers to easily add advanced indexing and search facilities to their own applications. It supports the Probabilistic Information Retrieval model and also a rich set of boolean query operators. Omega is a Web search application built upon the Xapian library. It can index a Web server's document tree (including HTML, PDF, OpenOffice, MS Word/Excel/Powerpoint/Works, WordPerfect, RTF, PS, etc.), or data exported from arbitrary sources (e.g. SQL databases).
mojoPortal is a cross-platform object oriented Web site framework. It supports PostgreSQL, MySQL, Firebird, SQLite and MS SQL for the backend. It includes a content management system, forums, blogs, photo galleries, newsletter, polls, surveys, an event calendar, an RSS feed aggregator, and a skinnable design.
Smuxi is an irssi-inspired, flexible, user-friendly, and cross-platform IRC client for sophisticated users. Smuxi is based on the client-server model: The core application (engine) can be placed onto a server which is connected to the Internet around-the-clock; one or more frontends then connect to the core. This allows the connection to IRC to be kept up even when all frontends have been closed. The combination of screen and irssi served as the example for this architecture. Smuxi also supports the regular single application mode. This behaves like a typical IRC client; it doesn't need separate core management and utilizes a local engine that is used by the local frontend client.
Lasso (Liberty Alliance Single Sign On) is an implementation of the Liberty Alliance specifications. These specifications define protocols for federated identities, single sign-on, etc. Lasso supports ID-FF 1.2, SAML 2.0, and parts of ID-WSF. It provides both a C library and bindings for several languages (Python, Java, Perl, PHP 4, and PHP 5).
screen-scraper is a tool for extracting data from Web sites. It works much like a database that provides access to the information of the Web. It provides a graphical interface allowing you to designate URLs, data elements to be extracted, and scripting logic to traverse pages and work with scraped data. Once these items have been created, screen-scraper can be invoked from external languages such as .NET, Java, PHP, and Active Server Pages. It can be scheduled to scrape information at periodic intervals, and can automatically write extracted data to CSV files.