I have lost my key on multiple occasions. Finding always seems to be luck of the draw in a coat pocket. This is obviously careless on my part, but there have got to be many others like me.

Does anyone know of an RF locator device available. There has got to be some tool I can use to walk around the house and have it indicate I am within 5-10 feet of the damn thing.
Does anyone know what frequency it transmits ?
anyone know of an rf frequency locator ?