Yeah. Frankly, if someone is that determined to harvest a bunch of random users, nothing can stop them.

Technically, sure; it is possible to set up an ultra-sensitive snooping system. In an urban environment, you might be lucky and get a range of a couple of hundred metres, but not often, and not in built-up areas with a lot of reinforced concrete. And sending your signal in is one thing; picking up a standard Centrino laptop from that distance may require considerable care and technical design.

And again, if you want things that badly, you probably don't want just a few drive-by coffee drinkers. You probably want a specific target - the CFO of a large corporation, maybe, or the systems admin chief.

To be honest, I think it would be easier to sound his fire alarm and steal his PC!

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