Much to the chagrin of my wife, after the Emily was born I signed up for Amazon Prime. For $79/year Amazon will ship just about everything to you second day and will overnight items for around $3.99 (although some items like books are usually $1.99). She did not like the idea of paying $79 for shipping for the year, but I knew that with a baby in the house getting out to pick up non-essentials was going to be a real hassle.
I doubt I have changed her mind yet, but I have to say I am happy with the choice. It has really come in handy in just the first three months. No guarantee, but since we always seem to be part of the crazy people shopping at the last second for holiday gifts, I am pretty sure she will see the light in December. :)