Sparkbox (http://www.icyblaze.com/sparkbox) from IcyBlaze is new software designed to help you organize your daily image collections, including screenshots, shared images from Dribbble, flickr, etc. It’s compatible with Mac OS X 10.7 (“Lion”) and is currently available in a beta version.
With Sparkbox you can drag and drop images to capture them. There’s a tagging system with an independent tag manage panel.
You can also rank your images. Sparkbox lets you search images by title and even color.