This sign can be used to mean such things as enthusiasm, motivation,
and/or caffeine.
No, I'm not making that "caffeine" bit up. The "Starbucks" crowd
have to have ways of discussing their habits and it seems they get
their daily motivation from a cup of coffee.
Rub your hands together "enthusiastically."
ENTHUSIASM = "caffeine"
See:
MOTIVATION
You can learn
American Sign Language (ASL) online at American Sign Language University ™
ASL resources by Lifeprint.com © Dr. William Vicars