Soda. Pop. Cola. Coke. Chilled carbonated beverage. Whatever you want to call it, it's my primary source of caffeine. Blame it on my Southern upbringing, where even a Pepsi is a Coke. Coffee did not enter my beverage vernacular until moving north. I'm slowly weaning myself onto coffee, but if you need me to be cognizant in a hurry, I need the tingly sensation of carbonation on my tongue.