A blue Vanda. Blue is the rarest color in the orchid family, and even the blue Vandas only approach blue by way of violet.
A Dendrobium hybrid.
A Stanhopea, whose incredibly complex flowers have clever mechanics that trap the pollinating insect until it has done its job very thoroughly.
Probably some sort of Laeliocattleya hybrid.
The Cathedral of Learning from three different angles. Pittsburgh is a bit unusual in having one of its tallest skyscrapers outside the main skyscraper district. Currently this is our seventh-tallest building (at 535 feet), but it will be bumped down to eighth-tallest when the new Tower at PNC Plaza (554 feet tall) is finished.