My family lives on Emergen-C. In fact, I probably need to go take some right now. We always use it when we travel or have important weeks (like choir concerts or musicals). It's not cheap though!

MySavings has instructions how you can get it "free" at Target this week combining coupons. Essentially you print out a couple of coupons from Emergen-C and then buy 2 boxes to get a $5 Target gift card. But you have to get the right coupons and the right sizes to make it work. I don't think it would work online, only in-store. But if you are a Target shopper anyway, it might be worth it!

Free Emergen-C at Target with Coupons