WorldCat has launched a new visual way of searching that allows you to show connections amongst related concepts. This tool is restricted to names at the moment. Below is a graphical representation for Nietzsche:
This is a particularly new approach, since similar visually-based search engines have been around for a while (e.g., LivePlasma and TouchGraph), but it has the added benefit of precision with the use of its name authority files. I’ll certainly be demonstrating this tool in my cataloguing classes.