[pearkes]

Hot water with lemon and honey is easy and warms you up. If you feel more adventurous, non-alcoholic hot cider.

[salemh]

I'd add, cinnamon naturally "perks" one up for the most part. I used to add cinnamon to my coffee (to avoid sugar), but works as well for tea, or your hot water, lemon and honey for a non-caffeinated morning (or afternoon slog) beverage.

http://en.wikipedia.org/wiki/Cinnamon#Medicinal_value

It has insulin "mimicking" effects, which could be part of the "boost" I feel.