"On-Site" is the fashionably obscure title of the current Museum of Modern Art exhibition on new architecture in Spain. How new? The show features projects that are either under construction or were completed in the past eight years. That coincides with the opening of what, for most Americans, must be the benchmark of modern Spanish architecture: the Guggenheim Museum in Bilbao (at right). Of course, there was notable homegrown architecture at the 1992 World's Fair in Seville and the Olympic Games in Barcelona, but it was Frank Gehry's titanium artichoke that put the country squarely in the international spotlight. Although "On-Site" is an architectural version of New York City's Fashion Week—long on visual excitement, short on intellectual content—there are plenty of projects worth examining.