Amongst the many many many things that made me decide as a kid that films just couldn’t ever get better than Starwars (now called “Episode IV a new hope”), was the scene when Princess Laya appeared as a hologram from R2D2 and chanted “Help me Obi-Wan Kenobi, your our only hope…” I thought about how cool a thing like that would be in real life (along with Light Sabers, Wookies, Imperial Star Destroyers and the like) Check this out – they now exist!

More info here:
Touchscreen Computer Display Floats in Mid-Air