Growing cress in a keyboard

I want to try this but it might be best to give it a go when I've got my own keyboard। Flick off the keys on your keyboards using a flat ended screw driver, put a thin layer of cotton wool between where the keys attatch to the board. Replace the keys and then sprinkle cress seeds evenly across the board (not unevenly, I've seen pictures where the cress growth is concentrated in places and it kinda looks untidy in my opinion).Water every other day using a plant mister, bingo.

I've heard another idea about cress growing as a practical joke; if you have access to someone's house whilst they've gone on holiday for a two weeks or so, sprinkle loads of cress seeds all over their living room carpet and water with a 'flowerhead' watering can or a plant mister. Hopefully by the time they come back there will be a crop of cress. Not tried this out either unfortunately.