Zeth at command line warriors has launched a campaign for laptop users to encrypt their home directories.
I don't encrypt my laptop, but I also never let it leave my personal proximity. Yes, I bring it into dunkin donuts when I get my coffee, and I bring it into restaurants with me, and so on.
My macbook doesn't have encryption acceleration, but laptops like the Everex NC1501 with the VIA C7 CPU have encryption acceleration, and combined with the OCF-Linux patches, an encrypted home directory should have very little performance impact, if any.
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