Actually, the idea of OSGi has been running in my head for a long time. I discovered OSGi when working on the embedded Cocoon, as we had to make an OSGi bundle with it so that it can be added to an OSGi-powered system in a car. OSGi is widely used in embedded systems, especially automotive and intelligent gateways.
Then came the interesting convergence between embedded system and "normal" systems when the Eclipse folks decided to trash their proprietary kernel in 3.0 in favor of OSGi. The resulting kernel has two layers: OSGi takes care of all classloading stuff whereas the Eclipse plugin system takes manages extension points and the associated plumbing.
When learning to write Eclipse plugins a while ago, I found some interesting similarities between what Eclipse provides and the Avalon semantics we're used to. Writing plugins is amazingly easy. Firstly because Eclipse provides an incredible PDE (plugin development environment) that guides you through the various tasks needed to write a plugin. And secondly because each plugin being isolated in its own classloader, there are a lot of issues that go away. For example, using static attributes is no more a problem!
Off topic, but it made me think of Sun's F1 work http://www.jini.org/nonav/meetings/eighth/J8abstracts.html#Cars
There's also work on Jini and OSGi going on ... which may have an interesting boost now that Jini is being relicensed under the Apache 2.0 license.
Cheers, Thor HW
