For me, I like my "futuristic" buildings to be restrained, so they age well. Too out-there, and they'll become dated very quickly.
One of my favorites is right here at home: Pier 1 Place, the world headquarters of Pier 1 Imports in downtown Fort Worth, Texas. It's like Art Deco from the year 3000:
Edit: And you gotta love that night lighting:
This photo by John T. Roberts of
Fort Worth Architecture.