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
Rub your hands together "enthusiastically."
There isn't "one" definitive sign for "caffeine." Many people just
spell it (or rather they spell something close to it.) Plus there
are some cute or interesting signs for CAFFEINE. For example, there
is a sign that is done in front of the eyes that starts as "S" hands
that change into "C" hands representing the widening of the eyes and
"alertness" that happens to people after they consume caffeine.
You can learn
American Sign Language (ASL) online at American Sign Language University ™
ASL resources by Lifeprint.com © Dr. William Vicars