How ironic. I just started regularly drinking coffee this last month for the first time in my life. I have about a cup (8 oz.) every other day. It does supply a bit of a jolt, but not enough to make me crash.
Otherwise, I only occasionally drink tea and I don't drink sodas anymore.
Smeth, you may want to give sparkling juice a shot. Things like
Izze that have no processed sugars, no preservatives, no artificial flavors and no caffeine could supply you with your fizz experience without such ill effects. I like the blackberry flavor, but my pseudo-gf swears by the pomegranate.