P.E.A.R. has done research on how human consciousness affects machines. Though it's not exactly light reading.
http://www.princeton.edu/~pear/publications.htmlThen there's the RetroPsychoKinesis project (
http://www.fourmilab.ch/rpkp/ ) looking at the effect of intent on probability.
And I think modern traffic lights have a sensor that ambulances trip when they enter an intersection, so there's a chance of subconsciously doing something that could affect that as well.
Really, though, I'd have to say there are infinite ways to do anything. The above doesn't even scratch the surface. I'm sure there's a few people with servitors who follow them around changing traffic lights, or maybe they summoned a demon who...
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