Here’s something I hadn’t seen before: Tabtastic uses
JavaScript, CSS, and semantic markup to implement a tabbed navigation interface. Since the tabs are all pulled from the
same page, navigation between them is instantaneous.

The nice thing about this is that it degrades gracefully. If you disable JavaScript, you get a nicely-styled page that
has headings instead of tabs, and links at the top of the page to skip to each section. If you disable both JavaScript
and CSS, you get a usable no-frills HTML page with headings and sections instead of tabs.

You can also bookmark a specific tab, so they’ve eliminated almost all of the disadvantages of using a system like
this.

[Via The JavaScript Weblog]