The uncontrollable feeling of constant discomfort, triggering a necessity for constant motion. Usually encountered during the morning after a night of drinking. The Shiftys are not a hangover, though they sometimes are a symptom of morning-after Still-Drunk.
Also caused by crashing after copious amounts of caffeine.
Dude, I'm getting the Shiftys while driving, this is bad.
I have to keep moving, I have the Shiftys.
I don't care if you have the Shiftys, you can't hang your legs out the window of my car!