Yes! I marvel at both the really complex designs and the the simplest ones (fewer parts!). Humans can do some really wonderful things when we put our minds to it. It's a shame we waste so much time and energy on non-constructive and destructive things. :/
Someone once put how fuel efficient gasoline cars are in perspective by saying that if a car gets for example 20 miles per gallon, imagine taking a gallon of a liquid and releasing a very small stream of that liquid to cover a 20 mile distance. Considering that many cars today do 30-35 mpg and higher, it's really amazing!