The alternative is to make my own syrups in diet and regular and keep them in my reusable flip top bottles. Vanilla or Cream Soda went over very well. I also like to add fruit juice, citrus wedges, or any combination of those. Housemade sodas are the new trend in some restoraunts as well. I also use any of those creations as a cocktail base.
Iced teas and iced coffee are also a common soft drink alternative. When I want something special I like to make a bubble tea with tapioca. You can see a descriptiona and recipe here. http://whatscookingamerica.net/BubbleTea.htm
I like to make different versions. Peppermint seems to be our favorite. I use mint green tea and favor my pearls by adding extract and sugar when cooking them. Yesterday my son used a citrus tea and we flavored the pearls with homemade lemon extract. We could have used lemonade instead of milk, he wanted milk.
I made an earl grey tea with vanilla pearls from my homemade extract.
I do realise that water is best. I also drink water from my filtered pitcher, but sometimes you want a sparkle or flavor or both.