This probably shouldn't be impossible, but I've never seen it:
Run a model train track about six feet off the floor all through your house, with trains that run on it all the time. Then when you're lounging in one end of the house and you hear somebody go to the kitchen you...
if impossible things had been invented than nothing would be impossible, i suppose there are good and bad things to that, cos it would mean that people would be able to do what ever they wanted, cos it would be possible, which means bad people would cause even worse deeds and...
I want the Better Coffee Pot. It would silently brew a fresh pot of coffee right by your bed so you wake up to the smell of coffee and it's right there - you don't even have to get out of bed. It would sense when you've had enough and you've left for your shower, and then it...
I want a Teleporter that can travel back in time.
Like Hiro in the TV series "Heroes"
I would teach my younger self how to be wiser.
I would undo my past.
Much as I learnt in the aftermath,
I wish it had never happened.