For My Dad

I often wonder about the idea that picking up a penny from the ground is not worth the energy it takes to do so. (This isn't my concept, I'm sure I read it somewhere or that someone mentioned it to me.) I assume this is figured out by the cost of food against the amount of energy needed to bend down, probably done using the slightly faulty unit of 'calories.' Also interesting, and a little easier to conceptualize, is the idea of something not being worth the time taken to do it.

Please note that the following has been taken from an xkcd comic; all credit for the mathematics involved and innovative view of the common concept goes to the author, Randall Munroe. (I'm assuming that the calculations are based on American standards, measurements, and money as of Fall 2011.)

If you spend nine minutes of your time to save a dollar, you're working for less than minimum wage.

And if you drive a typical car more than a mile out of your way for each penny you save on the per-gallon price, it doesn't matter how worthless your time is to you -- the gas to get you there and back costs more than you save.

However, what the above fails to consider is the enjoyment from 'saving.' Therefore there is potential that doing these things is entertainment to some and might actually be worth paying for, despite the apparent illogical aspect of doing so.