I've written before about temperature units.  There are lots of them, and they're not based around a useful zero point.  I hope one day we can come up with a better metric to quantify temperature.  Not only because the units are dumb, but because equal temperatures don't always feel the same.  Temps in the 80s (F) in a humid area feel much hotter than temps in the 80s (F) in a dry area.  Cooking on a metal tray takes a different amount of time than cooking with stone.  That has to do with thermal conductivity and other properties of materials, whereas meteorologists have a pseudo-hack called "feels like temperature".  That's cool and all, but it would be nice if we could come up with a way to rise above these variations. 

Same with Calories in food.  A Calorie is the measure of energy in the food itself.  But I think what would be more useful to know is the nutritional value.  That's obviously a whole other can of worms, but it would still be helpful to have an established metric that showed why fast food calories are not equivalent to real food calories.  (Update:  I'm not alone.) #math