Answers to a slippery question: Which lube do I use?

A teacher confronts a student outside the men's room near the end of the 1987 comedy classic "Summer School." The kid's been missing since the first day of class.

Teacher: Where you been?
Student: Men's room.
Teacher: For six weeks?
Student: My zipper got stuck.

A zany line, certainly, but it raises a larger question: what kind of lubricant should the kid have had on hand to free the stuck zipper?

Hint: it ain't WD-40.

What that boy needed was a can of silicone-based Jig-A-Loo. Petroleum-based WD-40 would've stained his Jordaches, but silicone comes off clean. Petroleum can also leave its mark on woodwork--if you still have grease spots where you "fixed" the squeaky cabinet hinges, you know what I mean.

In general, WD-40 works better as a solvent, a cleaner, a water displacer, and as a freer of seized nuts and bolts. Silicone lubes do better at the business of actual lubrication. They leave a slick dry film after they’re applied, whereas oil-based lubes quickly evaporate.

But if you're already spending six weeks in a bathroom stall, even silicone might be too slow.