Open-source firms are flourishing in databases (Ingres, for instance), business intelligence (JasperSoft), customer-relationship management and other business applications (SugarCRM, Alfresco).
Soon, IBM should be able to show how updates to the status of an opportunity in SugarCRM that we referred to earlier can be broadcast on an activity stream.
For example, at Lotusphere IBM showed an integration with SugarCRM that allowed an end user to create a meeting in Lotus Sametime or to store a document in Lotus Quickr.
This means that if you want to integrate your system with other systems, like your website or accounting database or if you want to perform complex customizations (and have the expertise to do so) you can dig into the entrails of SugarCRM to make it do exactly what you want it to do.