I am always looking for ways to make travel more convenient and conscious (since something has to make up for the 8 mile per gallon RV). Last Fall I heard about the Hydaway travel bottle at a local economic development event. I drink a lot of water while I travel, but also do not believe in buying bottled water or drinking out of the tiny cups given on planes. I am also not a fan of lugging around a nalgene or other metal/plastic bottle while traveling (small carry-ons preferred!). So, this collapsible cup has potential.
We used it on a recent trip to Chicago, capturing some great Bend water from the airport before boarding. With the increasing amount of drinking fountains that have water bottle fill stations, it is usable for each leg of the flight. I also had the flight attendant fill it on board (pat on the back for not using a plastic cup!).
Pros: light, collapses to fit in a purse, did not leak, holds enough water for a couple hour flight
Con: when it is full it does not fit in a small bag or in the airline seat pocket or just rolls around on the floor. I am going to augment with a carabiner to attach it to my bag going forward. This should also help once arriving at a destination and using walking around a destination.
Hydaway, 21 oz.: https://hydawaybottle.com