Akira is set in Neo Tokyo in the year 2019 - 31 years after World War 3. The artifact that I would bring to life is Kaneda’s motorcycle. From its description in the movie, it delivers 200hp at 12000 rpm with twin ceramic rotor drives on each wheel and computer controlled anti-lock brakes. (For reference, back in 1988, the fastest production motorcycle was the Kawasaki Tomcat ZX-10 which delivered 135hp)
According to the writer and director of the movie, Katsuhiro Otomo, he was inspired by the lightcycles from Tron that were designed by Syd Mead.