April Fools' pranks 2010

It wouldn't be April Fools' Day without the female friend who smiles and informs you she's devised the BEST PRANK EVER.

She's going to tell her boyfriend she's pregnant.

This is not a good idea. But tons of women do it every year.

Why isn't it funny? For starters, it has tremendous potential to put a guy in a state of paralyzing shock. It's one thing to say, "I got you a turkey sandwich instead of bologna. Hehe."

It's an entirely different deal to announce, "I'm bearing your child and our lives are going to change forever. Hehe."

In addition, the fake pregnancy is perhaps the April Fools' prank most likely to ignite a fight. The guy freaks out, the girl says she's kidding.

It should end there -- until you consider the female tendency to offer an innocent, "What would you do if I was REALLY pregnant, honey?"

Planning an April Fools' prank? Consider this wise Esquire tweet: "April Fools pranks should not include: saying you're pregnant, spilling, grooming supplies, anything involving your boss."

I'm sure Facebook's rise will make for all sorts of status updates involving fake pregnancies and engagements, too.

Weigh in with your best/worst April Fools' pranks.