Bottled water is expensive and creates tons of plastic waste. I've used the same bottle for years and saved hundreds of dollars.
Just got back from a short trip up the coast... was stressing about the train fare because I waited too long to book. Figured I'd eat the cost, but checked the app an hour before departure on a whim. The price had dropped by almost half for that specific time... grabbed it right there at the station. Felt like a weird, lucky little victory against the usual travel rush.
We spent half what we did last year by pre-packing from home.