Navbars are a great way to get a sense of the company's priorities, generally influenced by the biggest money makers.

Amazon's navbar in 2004: https://web.archive.org/web/20041102060756/http://www.amazon.... Books, clothing, electronics, toys/games, music, phones. Today, it's streaming video, streaming music, ["streamed"] ebooks, Kindles, apps ... and then (separated by a horizontal bar) Books / Audible (still plugging digital goods!), music/movies/games, electronics, home, etc.