It's time for the public to officially meet BOB [2]. "Bob" stands for "Building Outside the Box," in reference to the Frederic C. Hamilton building, otherwise known as that gravity-defying trapezoidal cluster of construction that will blossom into the expansion of the Denver Art Museum next fall as a geometric feat of architecture. Saturday's Building Outside the Box celebration is a free all-day event that include tours of the complex expansion project and a special exhibition. The focus is on celebrating architechture, particularly the people who are helping make the Daniel Libeskind-designed building a reality. It's a huge project for the art museum, and will be an international architechtural landmark for Denver. The design is truly amazing - like massive titanium crystals jutting out of 13th Street - and plenty of looky-loos are dying to get a first peek inside the progress. It's a free family event from 10 a.m. to 5 p.m. And admission to the Denver Art Museum's ongoing exhibits is free every Saturday, so this would be an ideal weekend to brush up on the arts.