Many ads at this time of year highlight the more traditional Easter egg.

But more and more ads are cropping up with a different kind of Easter egg.

An "Easter egg" is the term used by game developers for added, hidden content slipped into games to keep players amused.

Marketers are using similar Easter eggs in ads to encourage extra-close, repeat viewing.

The ads containing the most are from the Super Bowl, as in a 2012 Honda ad that replicates the movie Ferris Bueller's Day Off.

According to the agency that made the Honda ad, the spot is crammed with Easter eggs that Ferris fans would appreciate, like props and wardrobe pieces from the original movie, as well as clever messages on licence plates and phone screens.

In an online teaser ad for Old Spice that ran before the 2014 Super Bowl, a man and woman are checking each other out across a boardroom table during a boring meeting. Suddenly, the man's hair comes alive and scurries across the table to the woman. Amused, she writes her phone number on a sheet of paper, which the hair takes back to the man. The commercial ends with the Old Spice logo and "Hair that gets results."

When an eagle-eyed viewer noticed the phone number looked real and dialled it, he won tickets to the big game.

Super Bowl ads are so expensive that marketers will try anything to get more people watching and engaged, and many have turned to Easter eggs.

This Kia ad from the 2016 Super Bowl has just one hidden egg, but it's a fun one.

If you were alert, you got a giggle from the hidden pun at the beginning. The wife directs the husband to the "walk-in" closet, where he's surprised to find Christopher Walken.

In a nod to the computer game origins of Easter eggs, an ad for the Pokemon game from the 2016 Super Bowl was loaded with them.

A Pokemon character appears in graffiti on the side of a car, a flyer headline says "Learn to Surf HM3" which is a move from the game, and it goes on and on.

In another 2016 Super Bowl ad, we see Ant-Man break into Dr. Bruce Banner's lab and steal a can of Coke Mini.

The spot contained its own Easter eggs — including an anger management book in the lab — and it helped promote an online contest that saw Easter eggs hidden throughout Coke's social media. If you found one, you won a prize.

Easter eggs are yet another way marketers apply digital tactics to heritage media like TV, in order to slow the steady decline of viewership and engagement.

Bruce Chambers is a syndicated advertising columnist for CBC Radio.