This video by Rob Bryanton succinctly explains the 10 spiral dimensions. While it is only a synopsis of the first chapter of the book, "Imagining the 10th Dimension," viewers gain a quick understanding of string theory.
While the content is good, the style of explanation is very unique. It reminds me of the UPS commercials, but with very interesting sound effects. For some reason I really enjoy the sound used when lines are drawn.