This is sooooo kewwwl! Aluminium Foam!

 My inner geek antenna went up when I read this story

it's actually more of an alloy than strictly aluminium...but still.....kewl!


http://www.wired.com/2014/12/aluminum-foam-trains/

Once this get put into full production, not just trains will be used.  THINK GAS MILEAGE on cars without giving up frame strength.