Trivia: When Ted and Robin are at the restaurant, they are accidentally sent a champagne glass with an engagement ring in. A man then claims the ring and proposes to his girlfriend. This couple really did get engaged on the show - the guy set up the surprise proposal, as his girlfriend thought they were just there as extras.
The Best Burger in New York - S4-E2
Trivia: The Goliath National Bank logo can be seen at the end of the end credits.
Trivia: Chris Elliott plays Mickey Aldrin, father of Lily Aldrin (Alyson Hannigan). In real life, Elliott is only 14 years older than Hannigan.
The Bracket - S3-E14
Trivia: If you look closely on The Bracket, on the lower right side, you can see that Oprah is on it but didn't make it past the first round.
Trivia: www.guyforceshiswifetodressinagarbagebagforthenextthreeyears.com is an actual website.
Trivia: Barney uses the line "Call me crazy, but child actors were way better back in the 80s." Neil Patrick Harris was a child actor in the 80s, most known for his role in Doogie Howser, M.D. (1989). After reciting his line, a brief clip of the theme song from Doogie Howser plays.
Blitzgiving - S6-E10
Trivia: During this episode we see a character called 'Blitz' who is played by Jorge Garcia. Jorge played the character Hurley on Lost. In the flashback of the events when Ted left the bar, Marshall asks everyone to shout out some random numbers. Jorge shouts out the numbers: 4, 8, 15, 16, 23 and 42. The exact same numbers that are a key point of Lost and the numbers Hurley played to win the lottery.
Last Forever: Part Two - S9-E24
Trivia: On their wedding day, Tracy shows up at McClaren's to meet up with Ted and the gang. While sitting at their usual table, Ted and Tracy kiss. Right when that happens, we quickly see Marshall hand Lily some money. This is a callback to a bet they made in season 7, when Lily bets Marshall that Ted and Robin don't end up together.
Trivia: Ted is from Ohio, as is Josh Radnor who plays him. Similarly, Robin is from Vancouver, as is actress Cobie Smulders who plays her.
Trivia: Two of the cast's real-life spouses have recurring roles on the show. Alyson Hannigan is married to Alexis Denisof, who plays Sandy Rivers (the news reporter who works with Robin). Neil Patrick Harris is married to David Burtka, who plays Scooter (the guy who is obsessed with Lily).
The Best Burger in New York - S4-E2
Trivia: When the gang are in a taxi on their way to one of the burger joints with a green door and a red neon sign, look closely at Cobie Smulders' eyes whilst Barney is talking to Lily about Goliath National Bank - she is almost falling asleep when her character is not meant to be sleepy. Watch as her eyes widen, desperately trying to stay awake.
