No needSimply wire up a second doorbell button in parallel to the first, and locate it under the mattress. The weight of you getting into bed will make it ring. If you do it exactly right, the initial pressure of you getting into bed will press the button (Ding!) and the matress will bend around the switchbox allowing the button to return (Dong!). Such careful positioning isn't necessary with one of the fully electronic doorbell units that do both the ding and the dong when the switch is pressed down.
(
Lumpbucket tekcubpmuL,
Tue 26 Feb 2002, 7:03,
archived)