I was pondering this while trying out Toshiba's Portege R600 (see image), which is a fantastically light system weighing in at just 773g, but preliminary tests suggest it will give users less than ninety minutes work from its standard battery pack.
Of course, the good point of having such a lightweight laptop is that you hardly notice you are carrying it. If your job involves giving presentations at customer sites, then battery life presumably doesn't matter too much - but then you would probably want a larger screen than the Portege's 12.1in display.
It seems to me that such ultra-slim models are in a way self-defeating; if you really need to work while away from a mains connection, then you are probably going to have to carry several fully-charged spare battery packs around with you - or else take a heavier laptop that boasts a longer battery life in the first place.
Perhaps better battery technology might improve the situation, but then again, perhaps not - modern laptops are stuffed full of drivers and background services that keep the system busy and using up more power than it needs to, even when the user isn't doing anything other than reading the screen.
The dream of an all-day laptop that doesn't require a course in body building before you can carry it around seems as far away as it ever has been.
A full review of the Toshiba Portege R600 will feature on VNUnet.com in the near future.
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