PHOTOS: Schmidhuber; Milla & Partner GmbH

Looking like bleached-white trees that might be found on the alien world in "Avatar," the Germany Pavilion's outsized canopies exemplified its Field of Ideas theme. Functioning as a decorative exterior element and as light and ventilation wells for the pavilion's galleries, the canopies are also equipped with flexible photovoltaic cells. The cells are laminated between clear plastic sheets, and attached to a delicate steel net, which acts as both structural support and electrical conductor for the energy generated. The cells produce electricity in a way similar to traditional solar cells, with one fascinating difference: They can capture light from any direction, and generate electricity even in hazy, overcast conditions. Even more intriguing, the electricity produced during the day is collected in an innovative storage system, then used to power a high-performance LED ring at night that lights the trees from below.

photos: Dsp Productions

Guests entering the Mexico Pavilion are immediately met by staffers who hand them a sticker with a bar code on it that will accompany them throughout their visit. Taking it to one of 10 totems – or kiosks – with interactive screens, guests choose one of three languages (Italian, English, or Spanish), scan the bar code, and have their photo taken. Once they finish, they're conferred with a virtual seed representing one of 20 different traditional Mexican crops such as corn or chili peppers. Attendees scan the sticker at any of multiple stations when they want to learn more about traditional cooking, say, or Mexican history, after which the information desired is emailed to them. As they exit, guests scan their stickers one last time to receive a personalized visa printed with their name, date of visit, and an image of the virtual crop they were assigned, as well as a code and password to download their photo from the pavilion's website – all of which neatly extends the pavilion experience.