Orange Pekoe Number 10, also called as Darjeeling Tea (as in Earl Grey Darjeeling), keeps me alert right from the first whiff off the cup. So, there's also some psychology involved. Cappuccino also keeps me alert. Espresso, Cappucino are safer on the stomach lining, for those that have problems with hyperacidity, than instant or other brewed coffees.
Basically, you need to hype up the process of consumption of the brew. So, some ceremony is useful, like tea pots, and tea trays, and little nibbles and snacks, scones and biscuits. It also helps to keep consumption to a safe daily limit; as otherwise, you'll be downing limitless cups a day. Believe me, I've drunk tea like two cups every hour for the first three hours, and a cup an hour thereafter for eight more, and apart from the caffeine buzz, there's little to recommend over three, four cups a day max.
If you are drinking lots of tea, coffee; then it'll make sense to substitute sugar with Stevia or some artificial sweetener, just to cut down on the calories. Also, stop drinking tea, coffee six hours prior to sleep time, or you'll find difficulty in sleeping. If you are extremely sleepy, you will sleep even if you've gulped down a cuppa an hour before. But, on a normal day, I've found that drinking coffee, especially restaurant brews, invariably pushed my sleep time six hours down the line.
This is the safest, drug-free, healthy method to stay alert and in full control of your faculties. It's also anti-ageing, and prevents several diseases like Parkinson's, etc. Tea, cofee drinkers also imbibe less or no alcohol, so that's another indirect positivity.
Basically there are plus poimts all the way for this practice. So, go ahead and indulge!
Interesting post, thanks!