Bite the Bullet

One time back in college, a classmate of mine was stressed out over a test that he hadn't prepared for, and shortly before the exam began he told me that it was time to bite the bullet.  I told him that biting a bullet would be a pretty lame attempt at getting out of a test.  Sure, he'd probably end up chipping at least a couple of teeth and would have to go to the dentist's for an emergency visit, but he'd still have to take the test eventually.  Plus, if the bullet casing broke, he'd end up with a mouthful of gunpowder, and that's just nasty.  Some people will do anything to get out of taking a test.