Genki (the metric utilized in my drink rating system), is a Japanese word meaning both "happy" and "healthy," and is used as a common greeting in Japan.

Energy drinks have been extremely popular in Asia, particularly Thailand and Japan, since the 1960's, where they are still generally manufactured by pharmaceutical companies today. Energy drinks in Japan can cost upwards of $25 US, and include ingredients such as seal testicles.

Red Bull (the Western type) was first produced in Austria in 1987, and is currently available in over 100 countries (though it can be hard to find in Asia). It has also never killed anyone, and only contains caffeine equal to a typical cup of coffee.

A mild laxative, milk thistle has been shown to help detoxify and regenerate the liver, meaning that it's great for hangovers.

Also known as Vitamin B5, pantothenic acid is essential to the body and found naturally in all kinds of food. It helps reduce stress by helping the adrenal glands to produce the proper hormones during times of strain.

Naturally manufactured in the body from glucose, d-ribose is a 5-carbon sugar that helps relieve anxiety and stress and may even act as an anti-depressant. Unfortunately, it is non-sedative.

Despite the unwieldly name, this stuff is a naturally occuring metabolite that has been shown to improve energy levels and mental alertness. It is also a detoxifier, so helps with hangovers.

Contrary to what many people think, guarana is simply a natural source of caffeine (much like coffee), and has no different effect from the synthesized kind (though treehuggers will prefer it anyway). Note that caffeine is called guaranine if it comes from guarana. This stuff originally comes from Brazil, where it is a common flavor of tasty stimulant soda.

B12 also helps with red blood cell production, but increases energy to boot. It may also help to promote appetite and fight infections. It can also give you sweet dreams.

This stuff contributes in the production of seratonin (your brain's happiness chemical), red blood cells, and niacin. It can cause brain damage if taken in excess of 2000 mg/day, and gives you crazy vivid dreams. Good stuff.

L-carnitine, which is found in avocados, dairy, and meat, helps turn food into energy through a convoluted biological process I dont understand (though it has something to do with mitochondria).

A relatively effective muscle builder, creatine is also found in fish and beef. Creatine consumption can aid in increasing lean muscle mass, and some claim it provides energy as well.

Though never proven by western medical science to actually do anything, Asian peoples have been using this stuff to give them energy for millenia. Personally, I'm not a believer, but you can make your own call.

Though it is not essential to the body, (and thus not a vitamin) inositol is good for you in many ways, potentially helping fight cancer, eczema, hair loss, and depression.

Taurine is an amino acid derivative that was originally discovered in ox bile. It may have beneficial effects on the heart and digestive systems, possibly lowering blood pressure. It is most often found in cat food. Contrary to popular belief, nobody has ever shown that it gives energy.