John Cena once said, about Kane, that "He gets uneasy during the holidays and hates trips to the dentist." Glen Jacobs, the wrestler who portrays Kane, once had roles as Issac Yankem, DDS (a deranged dentist) and "The Christmas Creature."
Professional Wrestlers occasionally go out of their way to acknowledge real-life relatives, even if they're not officially related according to Kayfabe. An example of this would be Survivor Series 1987, where commentator Gorilla Monsoon comments on the prowess of referee Joey Marella, who was in fact Gorilla's son.
More infamously was the many non-references from Jerry "The King" Lawler towards his son, Brian Christopher. Lawler refused to acknowledge any kind of relationship with Christopher out of vanity; as someone trying to portray a suave ladies' man in his prime, he didn't want to appear old enough to have a 25-year-old son (he's just under sixty). His adamant on-air denials became a big open secret, and eventually a Running Gag.
When Stephanie McMahon's real life pregnancy was revealed on the air, Triple H (who was divorced from Stephanie in Kayfabe but was and is still married to her in RealLife) began gushingly speculating on what a stud the father must be.
When The Rock goes on a rant about how the Hurricane pales in comparison to other superheroes ("Batman could beat the Hurricane" etc.), the Hurricane responds with "there's one person The Hurricane can beat... The Scorpion King. Brendan Fraser beat the Scorpion King".
Wrestlers occasionally make references to previous gimmicks in this way, most famously Stone Cold Steve Austin using the Million Dollar Dream, his finisher as The Ringmaster, out of desperation at WrestleMania X-7.
In TNA, Kevin Nash was giving Jay Lethal suggestions for new nicknames. All of them were previously used by Nash.
As part of a Take That in a promo, Mickie James sarcastically said to Michelle McCool "you're so clever. Are you smarter than a 5th grader". Michelle made an appearance on the game show Are You Smarter Than a 5th Grader? and performed abysmally.
What makes the gag even more embarrassing for McCool is that she actually once was an elementary school teacher.
In the same promo, Michelle ribbed Maria Kanellis for her appearance on the Celebrity Apprentice.
One time on Sunday Night Heat, Todd Grisham compared Kane to Dr. Isaac Yankem. (Kane's old gimmick) Todd said to Josh Mathews, "Do you think they could be related?" Josh tries to change the subject by saying "I wasn't going to go there!"
Another one of his gimmicks was referenced by Jerry Lawler at a Christmas party when he said "he looks like some sort of Christmas Creature."
In a promo for his WrestleMania XV match with X-Pac, Shane Mc Mahon said "I'm going to pin you 1,2,3, kid."
While she was in WWE the second time around Gail Kim was referred to by the announcers as a 2-time Women's Champion. She held the WWE Women's Championship only once and the other title was in another company. One of the closest times WWE has ever come to acknowledging TNA on screen.
Torrie Wilson was once in an angle where she got in trouble for laughing at the Big Show backstage while he was in a bad mood. This was likely a reference to the famous WCW segment where Macho Man Randy Savage was on a rampage backstage and found Torrie Corpsing and slapped her in the face as a result.
When Freddie Prinze, Jr., was the guest host of Monday Night Raw, Santino Marella came down to the ring and imitated characters from some of Prinze's movies, including "The Fisherman" from I Know What You Did Last Summer. Marella also referred to Prinze's wife as a "werewolf-killer" - which is close but not quite accurate, since she's Sarah Michelle Gellar from Buffy the Vampire Slayer.
On an episode of 'Monday Night Raw a couple of years back, Chavo Guerrero was chasing Hornswoggle backstage and opened the door to a dressing room, expecting to find the midget inside - only to get smacked in the face by a swinging paint can on a string. Someone then emerged from the dressing room, and it turned out to be...Macaulay Culkin. (If you have to ask why that's funny, you should see this movie.)
In the final Highlander movie, Edge had a cameo as a highway robber. He's quickly defeated in a sword fight and then taunted with "Looks like you've lost your edge, lad."
