Google Image Swirl clusters the top image search results for more than 200,000 queries and it lets you explore the clusters and the relation between images.
"Once you find the group of images you're interested in, you can click on the thumbnail and a cluster of images will "swirl" into view. You can then further explore additional sub-groups within any cluster. Image Swirl expands on technologies developed for Similar Images and Picasa Face Recognition to discern how images should be grouped together and build hierarchies out of these groups. Each thumbnail on the initial results page represents an algorithmically-determined representative group of images with similar appearance and meaning. These aren't just the most relevant images — they are the most relevant groups of images," explains Google.
Try queries like: jaguar, flowers, van Gogh and keep in mind that this is an early demo, so not all the queries will return results.
Google has two other visualization tools: "wonder wheel" for exploring related searches and YouTube Warp, an interactive way to visualize related YouTube videos.
