The Silo Widgets plugin for WordPress introduces three widgets:

1. A Silo Pages widget, which outputs what amounts to an automatically generated navigation menu for your static pages.
2. A Silo Stub widget, which you can use as an inline widget when you'd like to automatically generate the contents of a page whose only purpose is to link to its children, e.g. this site's software page.
3. A Silo Map widget, which you can use as an inline widget to automatically output a full site map of your site; e.g. this site's site map page.

All three come in handy when creating silo structured web sites.

It is an exclusive plugin for Semiologic Pro users.