This almost doesn't seem real. Australia-based design and engineering firm Flux has developed the Flux Keyboard, a transparent keyboard that sits atop an HD display. The user can instantly change the labels for the keys, as well as background images for the keyboard.
The company describes the floating keys as "maglev keyswitches."
Here's how they work:
"Each key is suspended by two pairs of magnets which act as a spring providing the return force and a satisfying low friction travel in either tactile or linear switch varieties. The position of each key is sensed by hall effect sensors positioned underneath the screen."
"Hall effect sensors measure the strength of magnetic fields. They can be incredibly precise and are frequently used in applications where high reliability is a priority. The sensors used in the Flux Keyboard do not act like switches but rather can sense the precise position of each key."