Linux
http://www.linux.org/
FreeBSD
http://www.freebsd.org/
PostgreSQL
http://www.postgresql.org/
MySQL
http://www.mysql.org/
SAP DB
http://www.sapdb.org/
Hypersonic/Hsql
http://hsqldb.sourceforge.net/
McKoi
http://mckoi.com/database/
Xindice
http://xml.apache.org/xindice/
OJB
http://db.apache.org/ojb/
Hibernate
http://www.hibernate.org/
Castor
http://castor.exolab.org/
Torque
http://db.apache.org/torque/
JORM
http://jorm.objectweb.org/
XMLBeans
http://xml.apache.org/xmlbeans/
JiBX
http://jibx.sourceforge.net/
Castor
http://castor.exolab.org/
JAXB Reference Implementation
http://java.sun.com/xml/jaxb/
JaxMe
http://ws.apache.org/jaxme/
Tomcat
http://jakarta.apache.org/tomcat/
Jetty
http://jetty.mortbay.org/jetty/
JBoss
http://www.jboss.org/
Apache Geronimo
http://incubator.apache.org/projects/geronimo.html
JOnAS
http://jonas.objectweb.org/
OpenEJB
http://openejb.sourceforge.net/
OpenJMS
http://openjms.sourceforge.net/
JORAM
http://joram.objectweb.org/
JOTM
http://jotm.objectweb.org/
Struts
http://jakarta.apache.org/struts/
Cocoon
http://cocoon.apache.org/
Turbine
http://jakarta.apache.org/turbine/
Velocity
http://jakarta.apache.org/velocity/
Tapestry
http://jakarta.apache.org/tapestry/
WebWork
http://opensymphony.com/webwork/
Jetspeed
http://jakarta.apache.org/jetspeed/
Cocoon Portal
http://cocoon.apache.org/
Open For Business (OFBiz)
http://www.ofbiz.org/
Compiere
http://www.compiere.org/
InfoSapient
http://info-sapient.sourceforge.net/
JPOS
http://www.jpos.org/
Mercator
http://www.globalretailtech.com/
Cofax
http://www.cofax.org/
OpenCMS
http://www.opencms.org/opencms/
JasperReports
http://jasperreports.sourceforge.net/
DataVision
http://datavision.sourceforge.net/
JFreeReport
http://www.jfree.org/
JCharts
http://jcharts.sourceforge.net/
iText
http://www.lowagie.com/iText/
Apache FOP
http://xml.apache.org/fop/
POI
http://jakarta.apache.org/poi/
Cron
http://www.linux.org/
JCronTab
http://jcrontab.sourceforge.net/
Quartz
http://www.quartzscheduler.org/
Eclipse
http://www.eclipse.org/
NetBeans
http://www.netbeans.org/
SQuirreL
http://squirrel-sql.sourceforge.net/
TORA
http://www.globecom.se/tora/
DBVisualizer
http://www.minq.se/products/dbvis/
TOAD
http://www.toadsoft.com/
CVS
http://www.cvshome.org/
Subversion
http://subversion.tigris.org/
CVSWeb
http://www.freebsd.org/projects/cvsweb.html
ViewCVS
http://viewcvs.sourceforge.net/
DocBook
http://www.docbook.org/
OpenOffice
http://www.openoffice.org/
Structured Text
http://www.zope.org/Documentation/Articles/STX
MoinMoin Wiki
http://moin.sourceforge.net/
UseMod Wiki
http://www.usemod.com/cgi-bin/wiki.pl?UseModWiki
Jabber
http://www.jabber.org/
Mailman
http://www.gnu.org/software/mailman/
Eclipse Modeling Framework
http://www.eclipse.org/emf/
ArgoUML
http://argouml.tigris.org/
Poseidon Community Edition
http://www.gentleware.com/
XDoclet
http://xdoclet.sourceforge.net/
MiddleGen
http://boss.bekk.no/boss/middlegen/
Jostraca
http://www.jostraca.org/
JUnit
http://www.junit.org/
Cactus
http://jakarta.apache.org/cactus/
JMeter
http://jakarta.apache.org/jmeter/
Grinder
http://grinder.sourceforge.net/
Bugzilla
http://bugzilla.mozilla.org/
Scarab
http://scarab.tigris.org/
JIRA
http://www.atlassian.com/software/jira/
ITracker
http://www.cowsultants.com/
BeanShell
http://www.beanshell.org/
Jython
http://www.jython.org/
JRuby
http://jruby.sourceforge.net/
Groovy
http://groovy.codehaus.org/
AspectJ
http://eclipse.org/aspectj/
Ant
http://ant.apache.org/
Maven
http://maven.apache.org/
AntHill
http://www.urbancode.com/projects/anthill/
CruiseControl
http://cruisecontrol.sourceforge.net/