If you happened to drive by a particular condemned house in Houston in the summer of 2005, you might have seen it falling into a wormhole. Sculptors Dan Havel and Dean Ruck transformed two buildings owned by Art League Houston into this striking work of art for an installation called Inversion. For a short time until the houses' scheduled demolition, visitors could crawl through the tunnel to the other side, and passing drivers could jeopardize traffic safety with some serious rubbernecking.
Some galleries of the project can be found from Art League Houston, Kevin O'Mara, and Designverb.
Michael de Broin is a sculptor whose works typically embody a single concept in a visually striking way. For his outdoor scuplture Superficielle, a large rock which is obscured entirely by mirrors, that concept is the theme of transparency. Io9 picked up on this item as evidence of the development of new invisibility cloaking technology. They might have a point.