Transparent membrane-cable tensile structure from BASE Structures.Also from them, "Base structures sourced a high translucency silicon glass cloth, Atex 3000®, fabricated using special heat welding techniques, and this provided the client with a cost effective solution. "
Then there's the Denver Airport by Curtis Fentress. Greg mentioned these to me and I had forgotten that I'd seen these. A "catenary steel cable system", similar to the Brooklyn Bridge, supports a tensile fiberglass roof. 
Following these phrases, I searched tensile structures in Portland, and found one designed by Tension Structures of Eide Industries out of California, who did a nice structure atop the parking building of Rasmussen BMW.
