Whatever happened to the Slip?

Whatever happened to the slip? I can remember my Mom and my Aunt walking around in a slip after work. Women don't really wear slips anymore. If you do want a smooth sillouette under your dresses or skirts the picture 2 below is of a Spanx slip from Nordstroms. This great slip below on Elizabeth Taylor can be seen in Cat on a Hot Tin Roof. By the way it is a great movie.

Spanx slip available at Nordstroms, and http://www.nordstroms.com.