Being a big shopper at Costco and Sam's club, I've been a fan of Zip-fizz drink additives and have posted previously about them. I keep some with me at all times, and they have been a great help in my afternoon drudgeries from time to time.

Well, I found this item

http://www.bevology.com/superv.html

and after using one of their other products (energy +), I think I may switch to this one. Sometimes zip-fizz is a bit too strong, but something like this has similar nutrient values, and some different ones, but not so much stimulant. I like their portability too.