I like the single serving 5 calorie tubes for around the house and office, but still take Gatorade in the bush (kills three birds with one stone, for me). My method is simple - repack Gatorade into single-serving plastic cigar tubes (the kind with push-in caps). I get the perfectly-sized plastic tubes at Axman before they are touched by a cigar.

BTW, most dollar stores have 8-packs of the low-calorie tubes (for a dollar, of course). The Hawiian Punch varieties are my favorites.

-aj