This story about a professor of applied physics isn't real, but it sure is funny, and highlights the differences between practice and theory (which of course is much bigger in practice than in theory). I found it via Joanne Jacobs.

A typical Gaston exam question involves asking students to choose between catching a small metal box filled with 20 pounds of lead dropped from a height of 1 foot, or the same metal box stuffed with 20 pounds of feathers dropped from the roof of an 8-story building. Each year, about five students try to catch the feather-filled box and end up in the emergency room with concussions.

"I still think it was a trick," glowered Marvin Stoddmeyer, a student who chose the feathers and failed the final exam, breaking his collarbone in the process. "Gaston said something about momentum and kinetic versus potential energy or something during the year - yadda yadda yadda. But at no point did he specifically warn us not to try to catch a 20 pound object dropped from an 8-story building. That's deception, man."

And then at the end of the article:

Gaston did say he was willing to cut his students a deal and add 10 points to everyone's grade before applying a curve to the final grades.

"Now that's fair," said Brandon Marlowe, one of Gaston's students. "At least he's being honest with us."