Amazon has a sale on the 32-oz Takeya Vacuum-Insulated Stainless-Steel Water Bottle. It’s [amazon_link asins=’B0188QB9S4′ template=’PriceLink’ store=’boingboing’ marketplace=’US’ link_id=’872868eb-bfb2-4dfa-9d58-6e058f532e2d’]. It’s got a one-hand-operated drinking spout, and you can unscrew the lid to rinse and dry the inside of the bottle. Cold water stays cold for many hours, in my experience.