Whilst sitting in the hairdressers last week I thought how cool it would be to see how my hair looked before and after. Building on this idea I came up with the following solution.
First you replace the regular mirror, with a semi silvered mirror and place an LCD screen, and a camera behind it. When you first sit down the camera starts to record.
When you finish your haircut, you can switch on the LCD behind the mirror to display how you looked before, and even show a time lapse video of the cut in progress. The LCD can also be used as a time delay mirror, so that you can see the back of your head. Turn around once and the LCD will display your image with a 5 second delay, giving you a chance to examine the back of your air cut.
To build on this even further you could use the system to preview possible haircuts with a little image manipulation you could overlay different cuts in realtime over your reflected image, never get a bad cut again and if by some small chance it does you can keep the time lapse video of the destruction for posterity.
OK now just to go and build this thing.