It would be possible but you are dreaming if you want 10 hours out of laptop batteries, might as well use the AC adapter or a car lighter adapter. Not even new laptops can go 10 hours on a charge. Remember these batteries have a limited life the chemicals inside break down and can not recover unless replaced with new chemicals. Simple chemistry and physics. I looked at the site, it is nothing but a big battery, kind of like sliming down your car battery and carry it with you. It is basically a large portable Lithium-ion battery. I think it would be cheaper to find a auto adapter for your PowerBook unless you fly a lot then a portable powersupply might help. -- Your favorite stores, helpful shopping tools and great gift ideas. Experience the convenience of buying online with Shop at Netscape! http://shopnow.netscape.com/