I haven't really used them except to store legit content when we replaced some stuff for April Fools.
My purposes for static pages is pretty mundane. I intend to use pages to store Rules (Servers, Team Speak, Forums) and the about type pages. Things that don't change very often and will have links to direct threads to update specific information more often.
Its quite nice to have as a core feature. On vB the original site managers had a plugin called BF Easy Pages and they were using it for pretty much the same purpose. I just need to complete my Nav Manager plugin before I intend to add more links to our drop downs.