Will temperature changes cause a beer to "skunk" or otherwise spoil? In my fraternity days, there was a constant fear of beer (typically kegged but also bottled) getting "skunked" as a result of warming up and cooling down too many times, possibly even once.

Do non-extreme temperature changes such as moving a beer back and forth from a counter to a refrigerator cause perceptible changes to beer?  If not, what about more extreme changes, such as sitting in the bed of a truck or a trunk?  I'm aware that light has a degrading affect on it's own, so let's assume this beer is in a keg or a light-proof box.
In short, no.

As explained by George de Piro, a biochemist and Brewmaster of C. H. Evans Brewing Company—


  When light hits beer, it provides the energy necessary to drive a reaction that transforms the iso-alpha-acids into 3-methyl-2-butene-1-thiol. The “thiol” part of that somewhat cumbersome name indicates that there is sulfur present. Sulfur compounds often have strong, offensive aromas. Some musteline animals, like skunks, have evolved the ability to produce this chemical, and use it for self-defense. [...] This photochemical reaction is the only cause of skunked beer. Warm storage, while damaging to the flavor of beer, does not skunk it. Cycling the temperature of beer from warm to cold and back again is also not implicated. Storing beer in the dark is the simple way to prevent skunking.


It's actually pretty amazing how quickly this reaction can happen! From the same article,


  The photochemical reaction that skunks beer occurs very quickly; a well-hopped beer in clear glass can become noticeably offensive with just 30 seconds of exposure to sunshine. 


To wrap it up,


  Since light is an essential ingredient in the skunking process, beers packaged in kegs, cans, and opaque bottles cannot be skunked.


Here's the most detailed experiment I could find—The Impact of Lightstruck and Stale Character in Beers on their Perceived Quality: A Consumer Study.