Someone gave my mum one the other day, she didn't want it so she gave it to me. One of these Red Bull rip-offs... and it was awful! I drank it over an hour whilst I played some games of Pool, and I ended up with a bastarding headache, I felt dizzy, I couldn't focus or see straight, I was extremely cold, and I was shaking slightly.
I can finish off six cans of coke (1.98 litres) in an hour and feel perfectly fine, but not a single 500ml bottle of energy drink. Eugh.