One Way Colour Tunnel by Olafur Eliasson. This is a tunnel made up of light-shattering translucent and reflective triangular panels of coated acrylic, iresembling a walkway of stained glass. This is at the San Francisco Museum of Modern Art.
Measure by Fabrice Le Nezet - a concrete and metal physical representation of the idea of measure. "The objective was to 'materialize' tension in a sense, to make the notions of weight, distance and angle palpable.