IBM has added technology to its ThinkPad notebooks that will lock up--and protect--the hard drive when it senses the device is in the midst of falling, the company said.

The Armonk, N.Y.-based computer maker has rolled out two new ThinkPad models with the new data protection feature: the ThinkPad R50, with a list price of $1,350, and the ThinkPad T41, which has a list of $1,550.

The company says the Active Protection System technology is similar to what is used in cars to deploy air bags during a crash. A microchip is built onto the system board to detect when a system accelerates, which likely means the notebook is falling or being dropped, and then temporarily freezes the hard drive's read/write head until the system shows it has stabilized, IBM said.

Robert Enochs, IBM's segment marketing manager for the ThinkPad P Series, said the addition of the new technology will not add to the overall cost of the systems.

"Because we are so confident in the function of this feature, we actually expect to see a decrease in our warranty expenses," Enochs said. "So we can provide this to our customers at little or no cost."

Initially, the two new models will be the only ones in the ThinkPad lineup with the data-protection solution, but Enochs said it could be expanded into other models as well.

The T41 model is aimed at more mobile users, while the R50 is designed for "users who might take work home for the evening, but maybe they are not traveling as much," Enochs said.