When I heard this on Weekend Update on Saturday Night Live…I KNEW it was fake news.

Apparently not:

Self-Cleaning Underwear Goes Weeks Without Washing.
Self-cleaning fabrics could revolutionize the sport apparel industry. The technology, created by scientists working for the U.S. Air Force, has already been used to create t-shirts and underwear that can be worn hygenically for weeks without washing.

The new technology attaches nanoparticles to clothing fibers using microwaves. Then, chemicals that can repel water, oil and bacteria are directly bound to the nanoparticles. These two elements combine to create a protective coating on the fibers of the material.