The ASF is made up of nearly 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 OFBiz (The Apache Open For Business Project) is an open source enterprise automation software project
Apache OFBiz (The Apache Open For Business Project) is an open source enterprise automation software project. By open source enterprise automation we mean: Open Source ERP, Open Source CRM, Open Source E-Business / E-Commerce, Open Source SCM, Open Source MRP, Open Source CMMS/EAM, and so on. It is one of the few apps of this type to be developed by a community, rather than one corporation.
A distributed computing platform.
Hadoop is a distributed computing platform. This includes the Hadoop Distributed Filesystem (HDFS) and an implementation of MapReduce.
Apache Axis2 is a service hosting and consumption framework that makes it easy to use SOAP and Web Services
Apache Axis2 is a toolkit for creating and using Web Services, including SOAP, MTOM, XML/HTTP and advanced WS-* standards such as WSRM and WSSecurity. Axis2 includes a very fast runtime engine, together with tooling support for WSDL and WS-Policy, and plugin support for WS-Addressing, WS-ReliableMessaging, WS-Security, WS-Eventing, WS-Transactions, WS-Trust and WS-SecureConversation. Axis2 runs either standalone or hosted in Tomcat or other servlet containers.