Breadcrumb Navigation with CSS Triangles at CSS Tricks is an interesting how-to.
Find What’s Common Between Two Facebook Users at Digital Inspiration explains how to compare the common elements between two Facebook accounts. And how to opt out.
Think vitamin has a series of video tutorials on accessibility underway. These videos would be great in a classroom to help introduce concepts and techniques. Here one of the series: Accessibility Fundamentals: Visual Part I. Links to others in the series are here.