Never knew about this feature. Apparently greater gods have been using this for a while. There is this neat feature in WP that allows you to make your URIs even nicer. Consider what is better

or this

In the first example WP is creating the post-slug automatically by using the title, I never bothered to edit it. Now after reading at LibaryPlanet I have seen the light and URIs are much nicer. Do yourself a favor and start editing those post-slugs.

End Note: This is only available in WP 1.2.