Dynolicious appears to be the first automotive performance meter available for the iPhone and iPod Touch. The app utilizes the iPhone's built-in accelerometer to measure the performance characteristics of any vehicle it's placed into.
Simply toss your iPhone into the nearest cupholder or cradle and Dynolicious will record your quarter-mile, 0-60 time, lateral Gs, horsepower, and a host of other statistics. The developers state accuracy within a tenth of a second and 1.5 mph.
Dynolicious is available in the iTunes Store for $12.99.