How much of a beating can a so-called rugged laptop actually take? We put four models through the paces. We subjected them to spills and tosses; we even drove over two of them with a 700-pound ATV. Here are the results.

DELL LATITUDE E6400 XFR

The shell of this fully rugged 8.5-pound laptop is made from PR-481, a composite used in military equipment. It still worked after we drove the ATV over it and doused it with muddy water, but the touchpad did get a bit sticky. One drawback: The battery lasted just five hours.
COST: $4,473

PANASONIC TOUGHBOOK 31

This new 8.2-pound magnesium alloy laptop barely winced during our ATV rollover test and survived being thrown into a pile of mud and ice. The Toughbook's 13.1-inch screen is an inch smaller than the Latitude's, but the battery lasted twice as long, about 10 hours.
COST: $3,799

HP ELITEBOOK 8440P

A less durable business rugged laptop, the 4.7-pound EliteBook has a magnesium alloy chassis and a 14-inch screen. When we threw it in the air, a light came on indicating that the hard disk had locked to prevent data loss. We used two upgraded batteries at once for 20 hours of juice.
COST: $979

LENOVO THINKPAD T410

The ThinkPad, also business rugged, survived our spill test, but it needed 15 minutes to dry out. The 5-pound laptop has a 14.1-inch screen and an interior "roll cage." Like the EliteBook, its hard drive locked when we threw it in the air. But its upgraded battery lasted just six hours.
COST: $1,115