Schemr is a development tool that makes it easier to document complicated CCK field schemas. It is a natural counterpart to Features. Where Features can be used to transport schemas between Dev and Live sites, Schemr can be used to describe them.
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The ImageSearchField module provides an image field that supports both user-uploaded images, image URLs, and images returned by image-search APIs (e.g. Google's Image Search API, the Amazon API, etc.). The image-search results are driven by plugins for the various APIs and thus can be extended by additional modules.