Seemingly conceptually similar to the iFree3D system that has been blogged earlier this week, Vis/Space [hfbk.net] is a client-server system to visually explore 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 with a orange cube handle. A click to the cube also toggles among several different possible layouts. More information can be found here.