Little bit of fun for today. Bit of pop science to go with your coffee break? A book called Imagining the Tenth Dimension , released last year by Rob Bryanton, outlines some theories about how dimensions work, including some stuff about how to fold the universe so you can visit other timelines.
The official website has an entertaining Flash animation with the basics from the first chapter, including a great little illustration of what a 3D person would look like to a 2D Flatlander. There is a text-only version of the site as well, but then you'd miss out on his soothing voice and the pics.
NB the theory he advances in the book and on the site is, by his own admission, not commonly accepted, but it is a cool piece of Flash, lasting about 10 minutes.