This page would look a lot spiffier if you downloaded a standards compliant web browser.

Navigational Blocks: Tangible Navigation of Digital Information
    ACM Conference on Computer Human Interaction (CHI) 2002
    Navigational Blocks provide a tangible user interface for
    applications such as information kiosks. Orientation,
    movement, and relative position of electronically and
    microprocessor augmented physical blocks support visitor
    querying, retrieving, understanding, navigation and
    exploration of an historical information database.