The Chemistry Development Kit (CDK) is a library of Java classes for chemo-, bioinformatics, computational chemistry, and chemometrics. It provides important algorithms like substructure search, SMILES, Gasteiger charges, QSAR descriptor calculation, 3D structure generation, 2D layout and rendering, many IO formats, atom typing, and more.
Vis/Space is a client-server system for visually exploring data structures in 3D virtual space. It allows the placement of various data sources in a three-dimensional environment. Custom search terms can be entered into a query field, or can be navigated to and from an existing object. All objects like images and "text screens" can be moved around. A single click on an image shows the full-resolution version in the foreground. Whole collections of images can be moved. A click to the cube also toggles among several different possible layouts. Data sources include search engines, microblogging, Wikipedia, image/video search, and 4chan.
Jim (Java Image Manager) is a program for managing your personal images (photos, etc.). While Jim is really easy to use, its tagging technology is quite powerful. A plugin system makes it easy extensible with new technologies. It runs on several operating systems (including Windows, Linux and many more); all you need is a Java Runtime Environment.
JImageView an image viewer with no extra features. It is essentially an image display plus a menu-bar which includes the following actions: Rotate (Clockwise, Counter Clockwise, Rotate Normal); Scale (Zoom In, Zoom Out, Zoom to fit, Zoom Normal); Mirror (Flip Horizontally, Flip Vertically, Flip Normal); Fullscreen display; Slideshow mode; and Print.
Kabeja is a Java library for parsing CAD data (i.e. Autodesk's DXF format) and converting to SVG (dxf2svg). You can use Kabeja from the command line or embed it into your application. It includes a plain DXF2SVGViewer and integration into the Cocoon XML Web development framework and the Inkscape SVG editor.