Admittedly, its not difficult to imagine a scenario where less CPU cycles result in less power drain and this method isn’t going to magically extend your battery life by much but its nice to see the theory tested to the extreme.

SecTheory.com took a notebook PC, a couple of browsers and measured the battery drain on the Top 100 Alexa sites. They then took the worst offenders, that is, the ones that took the most power drain, and blocked script and ads using NoScript and AdBlock Plus. The results were quite significant[...]

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