Grokker is a search tool that organizes results in a logical, zoom-able visual interface. By visually arranging data it's great for topic searches because it displays results with contextual relevancy. Trying to explain it is kind of silly– just go download the trial and see for yourself. It's the best visualization experience I've had since Newsmap. UPDATE: I had to uninstall this thing because it was creating a suspicious amount of network connections to its home server, even when the app wasn't running. Too bad because it's a great visualization.