KNIME Labs gives you the possibility to preview new features and plug-ins which add new functionality to KNIME but still are under development. The nodes provided here are not (yet) part of the stable KNIME version because the functionality and/or API may not be finalized.
To see how to get these plug-ins check out the installation section. Most of the plugin-ins come with a detailed description and some workflow example.
We hope to get you involved by reporting bugs and helping us generating examples and documentation.