Changing Number Terms

In a recent contest in The Washington Post, readers were asked to take an expression using a number, add or subtract one, and create a new definition:
The Year 2001 Problem: How to find jobs for all those programmers hired to solve the Year 2000 problem.
Catch-23: Complete the previous catch before proceeding to this step.
Fortune 501: Levi Strauss makes the list, but just by the seat of its pants.
Motel 5: If you're not there by midnight, they turn off the light.
Dressed to the Eights: Impeccably attired with white socks.
Six Brides for Seven Brothers: Someone's gonna get hurt!
Snow White and the Eight Dwarfs: The title, before they expelled Gassy.
Five Eyes: Other kids can be so cruel when you are Siamese twins, and one of you is wearing a monocle.
665: The mark on the forehead of Satan's slightly less evil brother, Ralph. 

Safety Tip

Safety Tip: Calculus and automobiles don't mix - never drink and derive

Biology Lab

A group of students had a biology lab. As a part of this lab they were supposed to scrape some bacteria off their teeth with a toothpick and then examine it under the microscope. But this one girl had some problems identifying her bacteria and asked the professor what they were. "Those are sperm cells."