$40k for a Chevrolet Volt or $499 (plus $29 a year) for an aftermarket system from Viper? This hack from a guy named Dave will set you back considerably less, relying on a cheap prepaid cellphone that has had its vibration motor surgically removed, replaced by a couple of leads triggering the car's starter. Now, whenever the phone receives a call it starts up the car -- a somewhat dodgy proposition if a telemarketer ever gets hold of your number, but an interesting solution nonetheless. Dave is also excited about the prospect of setting on timers and alarms on the handset to auto-start the car at regular intervals, while we're excited about the total cost of the project: $71.03. Why, that's barely enough to cover the gas our big blue Excursion burns while warming up in the morning.