I was a barrista in Starbucks as well as two mom and pop coffee shops over a period of six years.
My drink of choice is a triple Americano (three shots of espresso in a 12-16 oz glass with Hot water). That being said, if your looking for a kick in the ass, I'd reccomend a redeye, (2-3 shots of espresso in a cup of black coffee). I don't like to overbuzz on caffeine though, so generally I stick to the milder stuff.