Cell phone cradle

Picture a normal cell phone power cradle with an extra data line out. This line would then be connected to a special input jack in your house phone. When the cell phone is in the cradle, the house phone it’s connected to will ring instead of the cell phone. The house phone can also be connected to a normal landline, and set with different ringers for each line. The benefits of this are:
1) You can charge your cell phone while at home, and not have to worry about missing any calls if you leave the room.
2) This will stop you from losing calls as you wander around your house on your cell phone (this hasn't happened to me in a while, but in my old dorm room I would have to stand in the corner to be able to use my phone), because the cell phone will not be moved, only the house phone.
3) The bigger handsets used for house phones are usually more comfortable than cell phones for long conversations.