I created this drink back in the late 90s when I was younger. It remains one of my all time favourite drinks and predates the Red Bull and vodka craze by several years and is a far better way to get serious alcohol with caffeine. Much more flavourful and drinkable.
You need Mountain Dew (diet will work but is not as good) and 99 BlackBerries. Simply mix approximately 4 parts Mt. Dew for each part 99 Blackberries.
Be careful, this is one strong drink that tastes like Koolaid. The caffeine will keep you on your feet much longer than you would think and if you are not paying attention you could have over a dozen shots in you before you even realize that you are drinking. Very tasty and very potent. Remember that 99 Blackberries is 99 Proof! That is more than normal vodka or whisky. Mixing 4:1 makes it 20 Proof. So if you put this in a 20oz glass like most people do you are drinking 20oz of 20 Proof!!! (Read: one sip, two sip, three sip, floor.)