Saving big bucks in drinking water
Use a glass, or a clean empty bottle if you are about to travel and so choose.
Fill it from the tap (in most jurisdictions).
Much commercial bottled water, including Dasani and Aquafina, is sourced from municipal water suppluies.
Which are, in most jurisdictions, regulated much more stringently than commercially bottled water.
Think of all the money you'll save whiledrinking your 8 glasses daily!