Massdrop offers the Crimestopper Tire Pressure Monitoring System, model no. TP-70, for $84.99 plus $3.75 for shipping. That's the lowest total price we could find by $55. It monitors inflation, leaks, and tire temperature and includes four sensors which replace your tire stem caps and a digital display which plugs into your vehicle's 12-volt port. Deal ends May 29.
The expected shipping date is June 10.