Pictag is a simple web photo gallery with automatic thumbnail generation and tagging capability. It's self-contained in a single file, uses the filesystem for gallery layout, and requires no stand-alone database (it uses SQLite) or no database at all. It handles EXIF data, provides support for HTTP user authentication and authorization, and is customizable.
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.
SynScope is an offline visualization and alignment tool for time-varying signals acquired from multiple sources that may differ in offset and/or sample rate. SynScope allows you to define reference points that correspond to identical events between source pairs. It then estimates the offset and resample rate to link these sources. It maps sample time from one source to the other via a link equation. Signal alignment can be inspected with synchronous visualization or resampling. With synchronous visualization, linked signals scroll together according to the link relation. With resampling, linked signals are resampled to the highest sample rate and offset-compensated.