The ASF @ 15 - The Apache Software Foundation Celebrates 15 Years of Open Source Innovation and Community Leadership http://s.apache.org/wZr
... and cheered at ApacheCon Europe http://s.apache.org/1o4
The ASF is made up of more than 150 top level projects which cover a wide range of technologies. Chances are if you are looking for a rewarding experience in Open Source, you are going to find it here.
Apache XML Commons External provides an Apache-hosted set of SAX, DOM and JAXP interfaces for use in other xml-based projects.
The External components portion of Apache XML Commons contains interfaces that are defined by external standards organizations. For DOM, that's the W3C; for SAX it's David Megginson (http://www.saxproject.org); for JAXP it's Sun. While we could send users to each of the primary sources for these deliverables, keeping our own versions of these in the XML Commons repository gives us a number of advantages: 1) Simplicity of downloads; users get the whole product from one place, 2) Better version control; we can only take fixes we want and add Apache-specific changes, 3) Better overview documentation of how these interfaces fit into...
A library for developing geospatial applications.
Apache SIS provides data structures for geographic data and associated metadata along with methods to manipulate those data structures. The library is an implementation of GeoAPI interfaces and can be used for desktop or server applications.
RESTFul web services based on JAX-RS specification
Apache Wink is a simple yet solid framework for building RESTful Web services. It is comprised of a Server module and a Client module for developing and consuming RESTful Web services.