mod_auth_useragent2 is an Apache module that can be used to limit access to documents by means of the User-Agent. As an authentication method, this is really unsafe because it is easy to change the User-Agent in most browsers, but it could be used to prevent stupid bots and spiders from accessing your Web sites.
Isobel is a framework to build complex information retrieval and analysis systems. Isobel can be functionally divided in two subsytems, Isobel Gatherer (the crawling and filtering subsystem) and Isobel Analyzer (the analysis subsystem). The two subsytems can also be used separately. Isobel Gatherer offers ready-to-use services like content fetching, scheduling, document format conversion, Hyperlink graph storage and analysis, content storage and indexing. A programmer may easily add new services. Isobel Analyzer uses the IBM UIMA architecture to reuse the analysis components developed for this architecture.
Compass is a Java framework which makes it simple to map your Java object model into a search engine. It is built on top of the Lucene search engine. Compass features declarative mapping technology OSEM (similar to O/R database mapping), transaction management, Google-like query syntax, externalization of common metadata, and much much more.
Tapestry Palette is a plugin for Eclipse that builds upon the Spindle plugin. The palette provides a tree view of Tapestry component libraries, a component inspector to discover parameters available with links to HTML documentation, drag and drop addition of Tapestry component references to templates, and a Property Sheet for editing of component bindings. The plugin can be installed from within Eclipse via an update site.