Of late I've been working on a couple of Eclipse RCP based applications. The biggest problem I've run into is the lack of good example applications for the RCP. Either they are too big (the Eclipse IDE for example) or too small (the sample RCP application supplied with 3.1). Then I came across JLibrary.

JLibrary is large without being too large. It has example of most of the things you'd like to do with the RCP without the weight of the Eclipse IDE. If you're interested in using the RCP then I'd suggest checking it out.