Don’t like to lose space to an empty water bottle? Don’t blame you. End that nonsense with a collapsible water bottle ($18). The shell is soft plastic that’s BPA-free, PVC-free, and meets or exceeds FDA and EU regulations. Additional safety stuff: naturally anti-fungal, dishwasher safe, and backed by a lifetime warranty. When you’re out of water (or again, out of whatever), it folds down into a little disk. Pretty cool stuff.