The Hydro Flask water bottle is a great one to stay hydrated. The bottle was designed with a double wall which keeps hot liquid hot for 12 hours and cold liquid cold for 24 hours. These numbers may be a little exaggerated but the bottle still works extremely well. The double wall also stops the bottle from sweating when there is a cold substance inside. They carry a number of different models that host anything from coffee to water. These are also great on the move.