I've never been a hot drink person, prefering diet coke other than the occasional hot chocolate, but recently i've started to drink green tea, and probably cancel out any good it does by adding sweetener, but, what i have seen a few mentions of on here is marmite - half to full teaspoon in hot water - which i've yet to try, but it sounds lovely and and I think there might be reports of it actually having health benefits but i cant remember where i saw that so cant post a link i'm afraid.