openCRX
OpenCRX is a professional enterprise class open source customer relationship management solution. It is a fully featured CRM system that includes account management, product and price management, sales pipeline, activity management and issue tracking, groupware, and tools and administration. The groupware feature set includes email, contacts, and calendar scheduling. Because it's an open source project, OpenCRX can be downloaded under the BSD license, which allows anyone to use the software on the condition that its copyright and conditions of use are not removed. It can be modified to suit the needs of the end user. OpenCRX was developed by Chris Mueller, Werner Froidevaux, and Harald Burger with the help of dozens of other contributors. The source code can be found at Sourceforge.net.