The Webcrossing plugins server, which was not working for a while, is now working again. You can access it from your Control Panel > Shop for Plugins. So if you have a hosted site, or an up-to-date self-hosted site, you can now easily add new features to your site via plugins. There are many kinds of plugins you can make use of, including new folder items, UI features and extensions. They are all free, and automatically download and install from the plugins server.
If you don’t have access to a Webcrossing server control panel and want to browse the plugins available, you can also directly at http://plugins.webcrossing.com/plugins.