Walmart has the Goodyear Heavy Duty 120-volt Direct Drive Inflator for $39 with free shipping. Features a 150-psi output and comes with adapters for use with automotive tires, bike tires, sports balls, and mattresses.
Has good Amazon Reviews, where it sells for the same price.
eBay has the Rand McNally Tire Pressure Monitoring System for $50 with free shipping. List price: $80. Features wide temperature range sensors, can measure temperatures from -40°F to 257°F., wide pressure range sensors, can measures pressure from 0 to 80 psi., includes four valve cap sensors and a rechargeable TPMS receiver.
eBay has the Schumacher SSC1000A Battery Charger and Maintainer for $34 with free shipping. Retail price: $65. Has good Amazon Reviews.