All the plugins are located under "plugins" sub-directory. You can click the "plugins" toolbar button to access the list of the plugins. Just select one to execute from the drop down menu list.

Currently, plugins can be anything that can be opened or executed by windows shell. It can be a shortcut to a website, a link to an existing program file or document, an executable file, a web page, etc. Just put them under "plugins" directory and they will be immediately available from the plugins drop-down menu.