Beretta PX4 .40, and even with my new 92FS the PX4 will continue to get nightstand duty. It has proven itself 100% reliable over thousands of rounds in a wide variety of cleanliness and lubrication states, plus it has a rail for my Streamlight TLR-1S. I am too comfortable with it to abandon it as the nightstand primary, maybe ever. No matter how great my newest guns are when it comes to nightstand duty I want boring, old, broken-in ones.
Of course if I have a minute of warning I'll grab the 870 out of the closet, which is a whole different level of comfort.