XML Sitemap Generator
General settings in each component's 'Options'.
On/Off and priority settings in 'Meta Options' for each 'item/article' view.
I think that a Site-map component is a necessary on each website. I use a site-map on every website that I develop
This is greatr idea, but this depends on the URL construction schema. (SEF or non-SEF) I would suggest a simple plugin which is called on AfterRender, parsing the output for internal links and storing them.