Like coffee, tea is a good drink choice, as boiled water gets sterilized and is generally safe to drink. An even better option is tea brewed from bottled water.
Canned or bottled carbonated beverages, such as carbonated water and soft drinks, are safe drinking options, as the carbonation assures that the bottle has not been previously opened and refilled from the tap.
Bottled water is a safe drinking option, but make sure to check the seals on bottles to ensure they have not been refilled with tap water.
Beer, if served from a closed bottle or can, is a safe drinking option when traveling, though should clearly be consumed in moderation (and only be enjoyed if you are of legal drinking age, of course).
Like beer, wine is usually safe to drink if served from a closed bottle, though it too should be consumed in moderation (and only be enjoyed if you are of legal drinking age).