Dispensing Dyes onto Wool

Let's say you have a dispenser containing ink or any other kind of dye and a block of wool is in front of it. When activated it should change the colour of the wool to which ever colour of dye was dispensed.

You could have a floor of white wool (or maybe even carpets?) and underneath a level of dispensers then some kind of redstone to activate them all. This could then display any kind of pattern or image covering the floor based on the dyes used in each dispenser. Huge walls of white wool could be turned into giant images at the flick of a switch. or maybe you just changing the colour of your ceiling randomly with multiple dyes in each dispenser above it.

Apologies for my british spelling of "color/colour" and i placed this in redstone topic because it was about a possible new usage of the dispenser.

This is nothing important to advance the game, just an interesting extra I'd like to see.