Desktop search engines

I'll look at two open-source desktop search engines, imgSeek and Terrier, which are handy tools when I search image files and XML documents that contain text and references to images. I can use a rough sketch or import an image to query similar images from a bucket of hundreds of disparate images — almost like finding a needle or two in a haystack of images. The search results can bring up duplicate images, each with a different file name. In addition to query by content, I can look for images by metadata keywords, such as filename, description, and creation date.