Riding a bike is a cheap, environmentally friendly way to get from point A to point B. However, there is some maintenance to keep up with. You need to make sure you have functioning parts, and tires full of air. However, no one wants to carry a bike pump around for “just in case” scenarios.
If you’d rather not pay 25 cents at a gas station any time you need to plump up your tires a bit, you can opt for the “This Is A Bike Pump!” attachment. This little key chain will let you use any industrial air compressor to fill up your tires. There are car shops and fire stations every couple of blocks that have air compressors that likely won’t mind if you borrow a little air. This is a $12 purchase that is unobtrusive, and could come in quite handy.