Your caller presses the doorbell but instead of a standard-wired alert system, the array of wires leads to a fishtank panel inset in the door; each wire connects inside the tank to a series of slimline boxes with piano key lids. As the pulses trigger the keys, small amounts of food are released from a central hole in each. The fish are attracted and strike the keys, releasing random musical notes to alert you to your visitor's arrival.

It might not always be tuneful but it would certainly make the wait whilst you answer the door more entertaining.
-- Nelipot, Mar 20 2010

//a fishtank panel inset in the door; //...Once one gets past the physical maintenance problems of having a fishtank exposed to large quantities of natural light and daytime/nighttime temperature swings, I suppose that would also become a real deterrent to door-slamming, as well.
-- jurist, Mar 20 2010


ahmmm....Jurist, please excuse me...I know next to nothing about keeping fish.. what are the physical maintenance problems of having a fishtank exposed to large quantities of natural light and daytime/nighttime temperature swings,
-- senatorjam, Mar 20 2010


Too much light leads to rampant algae and tempertature differences lead to dead fishies.
-- 2 fries shy of a happy meal, Mar 20 2010


thanks
-- senatorjam, Mar 21 2010


\\no food = dead fish = food\\ But not fish-food.
Now, if it were an octopus instead of fishes, perhaps you could train it to play tunes.
-- mouseposture, Mar 21 2010



random, halfbakery