JavApi provides a collection of .NET classes in the form of the Java API. It thus allows you to use an identical API to develop for both platforms.
rpmspecmanager provides help for writing spec files to build RPMs. It works in a snippet-like style. The final goal is to manage a full project, including making the tar.bz2 archive and starting the build of the RPM.
An Eclipse Mylyn-Mantis plugin.
An image batch converter and resizer with advanced features.