• I think the comic that's gotten me the most feedback is actually the one about the stoplights. Noticing when the stoplights are in sync, or calculating the length of your strides between floor tiles - normal people notice that kind of stuff, but a certain kind of person will do some calculations.

    "Real Geek Heart Beats in Xkcd's Stick Figures" by Adrienne So, November 13, 2007.