I don't know if this counts but I like to measure, weigh and quantify things. When I buy a gun or knife I like to measure OAL, barrel or blade length and see how close it is to the literature claims. I also put things on my scale and calculate the muzzle energy of loads with the gravitational constant rounded up or down even though there is no practical difference - the standard deviation and mean spread are larger. At work I like calculating radius bends even though most of my friends prefer to avoid doing so.