Oil that cleans water. Pacemakers powered by our own blood. Drones that can spy on you in your backyard. Scientific American has chosen these and seven other innovations as the leading developments in 2012 that could ultimately change our world. The radical ideas are not pie-in-the-sky notions but practical breakthroughs that have been proved or prototyped and are poised to scale up greatly.

If youd like to hear more about the 10 innovations, ask questions or add your opinion about their potential, join me and Google Science Fair in a Google+ video Hangout on Tuesday, Nov. 20, at 2 p.m. Eastern time. Googles Hangout team, myself and guests will be visible on your computer screen as we discuss and debate the intriguing developments.

If youd like to join the event, please go to the hangout page to sign up. Or just tune in on Nov. 20 if you already have a Google+ page. And if youd like to read, ahead of time, the Scientific American print article that reveals the 10 innovations, its online free until Tuesday at 3:00 p.m. Hope to see you!

Image by The Heads of State