Yes,
Xhalin it does exist.
Awhile back, I had purchased a White Tea and Pomegranate flavored e-liquid.
I was getting tired and thinking of going to bed when I filled my tank with the stuff and started vaping it. Shortly after, I started to wake up a bit. Next day I emailed the place I got it from and asked them if it had any caffeine in it. They told me that it most likely did as both the tea and pomegranate were both net extracted flavors.
I would not go so far as saying that caffeinated e-liquids will ever replace a cup of strong coffee but with at least this one you could feel the effects.