Why don't telephones have timers? With all wireless handsets would it not be nice to have a phone timer in the main base unit.
You can then set the timer to turn the phone ringer off an on at particular times and the phone calls can be redirected to the answering machine.
You could set the timer to turn the ringer off during dinner time or during some TV show or while studying. It would avoid having to go to each and every phone in the house and turning the ringers off. Also at the end of the timer the phone ringers would automatically turn on and you don't have to remember that you had turned the ringer off.
Maybe it can be connected to TIVO and during your favorite programs you won't be disturbed by phone calls.

Advantages: Peace and quiet from phone calls at scheduled times.

Disadvantage: Another thing to program in addtion to the alarm clock and VCR.