If you know Blackberry development (which I don't!), you'll know that it's programmed in Java. Version 2.0 of C# wasn't that much actually different from Java because they were about 90-95% identical. Both languages have drifted apart somewhat with newer versions but still retain remarkable similarity.
A friend of mine Lennie De Villiers has a blackberry and wants to write C# code for it. Naturally it will need translating into Java so he has started a project to create a translator from C# that outputs Java that runs on your Blackberry.
My full-time job is in the kind of Enterprise environment that uses Blackberrys and develops Apps internally but I'm sure the C# developers there would welcome this. If you're interested in helping the project, contact Lennie via the Contribution Wanted Page.
- Link to C# Code Library