Challenge the technology
I think this is a rather simple idea. Use your idea about the capabilities of present day technology and make a projection what it can achieve by 2050. Based on that ask the technologists to give you three inventions. Be as creative as you may like to be but exclude pseudo science and techno fictions. I propose to each TEDster to be the Leonardo da Vinci of 2013.
Technologists and entrepreneurs! Have a look here and decide if you are up for the challenges.
Let me roll the ball first. I wish the following:
1. Edible clothes
2. Metals that grow and heal
3. Telekinetic robots