Wolfgang Gehner from Infonoia has posted an interesting article about using RCP/Equinox for server side applications. There are also discussion threads about the article on EclipseZone and The ServerSide.
There seems to be a lot of innovation developing around RCP and Equinox. This is a great example and it will be interesting to see how it develops. Developing server side applications using Eclipse is definitely an exciting idea.
btw, notice Wolfgang is based in Switzerland. I am telling you, Germany and Switzerland are hot beds for RCP.