@Soulfox -- Very true, but one should always have an air compressor handy. I keep mine in the trunk of my car and have used it often.
Things aren't like they used to be when we'd drive around with low tire pressure and not know it. These days, our cars tell us when our tires are low and nag us to fill them up with air. Since few service stations offer free air these days, an air compressor can save you a fortune in quarters in the spring and fall when temperatures fluctuate and we find ourselves needing to inflate our tires often.