Now your mileage will vary, but when it comes to mobile computing Hewlett-Packard made an intriguing announcement today.

It seems HP has finally figured out how to get almost a full day of usage out of a single charge on a notebook. The company has announced that one of its new EliteBook 6930p systems configured with a second a battery, a solid-state disk drive and an Illumi-Lite LCD display, is capable of running for a full 24 hours.

Of course, HP used a theoretical benchmark to come to the conclusion that this system could run 24 hours. In real life, that may not actually happen. But it's pretty clear the system could probably go for about 20 hours without recharging, which is roughly equivalent to three coast-to-coast flights, assuming of course, the planes are on schedule.

Customers can buy HP notebooks configured with Intel 80GB solid-state drives starting in October. Those systems can be configured with either Windows Vista or Windows XP.

Naturally, HP is touting this capability as another example of the company's commitment to be more energy-efficient. But when you get right down to it most people are sick and tired of carrying extra battery packs around. Fully configured, the EliteBook 6930p weighs in at about six and a half pounds. But unlike comparable systems, you might not have to carry around an extra pound or two of batteries just to make it the coast one way.

As much as the EliteBook 6930p might do for the environment, the truth is that there's probably a lot more interested among world weary travelers in losing the extra battery weight than there is in using less electricity.

Saving the environment is great. But saving a potential trip to the chiropractor is probably a whole lot better.