WSO2 is preparing for the first major release of their enterprise java product series after adapting the OSGI technology. You can already try out the betas from the wso2.org site.
- WSO2 Web Services Application Server (WSAS)
- WSO2 Enterprise Service Bus (ESB)
- WSO2 Registry
- WSO2 Business Process Server (BPS)
With the power of OSGI you will be able to customize these products for your need just by mixing and matching the components within these products. If you like to learn more about this, just have a loot at the following ebook released by WSO2.