Think of the targeted social engineering attacks you can do with this. If you know that an individual has access to a sensitive computer network you want access

Think of the targeted social engineering attacks you can do with this. If you know that an individual has access to a sensitive computer network you want access to, you can make them a targeted offer they can't refuse and point to a site with some malware rootkit or something. I'm sure there are endless devious tricks that can be pulled with this system, beyond your harmless pranks like these. Now that I'm aware of the possibility that an ad I see is only seen by me, I'm much less likely to trust them with a click.