Big Lipped Alligator Moment: Matt Hughes' decision to hold a Bible reading session, using it to compare himself to Queen Esther. Matt Serra, his bitter rival and opposing coach, certainly did not hold back his disdain for the act.
The decision in the Zapata/Stephens fight in TUF 19 may be one of the most bizarre, not only in TUF history, but UFC history. Most had Zapata winning via his wrestling domination, while some did give Stephens the nod due to doing more damage. Most importantly, two of the judges did; however, with a point deduction in the third sudden victory round on Stephens for an illegal elbow, it ended in a majority draw, and then the judges picked Stephens as the winner based on the fight overall. It was the first time anything like that had happened.
Broken Base: The show at first divided the hardcore base. Many thought the show was great for getting exposure of the sport to the mainstream (and/or just enjoyed the show), while others bemoaned the influx of noobs to the online forums who didn't know anything about the history of the sport or any fighters who weren't on the show (with a little It's Popular, Now It Sucks thrown in). Now, most have learned to accept the show or just completely ignore it.
Crowning Moment of Awesome: The exciting barn burner Light Heavyweight finale fight of Season 1 between Forrest Griffin and Stephan Bonnar. A fight so pivotal in the history of US MMA, Dana White constantly lists it as the reason The Ultimate Fighter got renewed after the first season and led to the rise of the sport's popularity in the US. Dana has even said despite Bonnar's increasingly poor record of late that he'll never fire him due to the fight.
Forrest and Stephan are now both retired, were inducted into the UFC Hall of Fame, and essentially have jobs with the UFC for life. One could argue Forrest could have entered on his other merits, but essentially, it's all because of THIS FIGHT.
Stephan Bonnar's comeback to Diego Sanchez' question, "Who are you, my dad?"
Dana showing up for the coach's challenge in Season 10 wearing a PRIDE t-shirt (Japan's PRIDE was once UFC's biggest organizational rival, since bought out by UFC after allegations of Yakuza involvement).
In Season 12's premiere, after the fourteen contestants have won their fights to get into the house, coach Josh Koscheck was eying Michael Johnson, an athletic and well-rounded wrestler. However, GSP knows that Koscheck will also want Marc Stevens, so he writes up a list of his supposed top picks with Stevens' name written in giant letters at the top, holding it so that Koscheck can see it. Koscheck's team wins the coin flip, so they choose to have first pick of the fighters, but Kos spies GSP's top pick and decides that he needs to secure Stevens with his first pick. GSP whispers, "It works!" to his coaches and proceeds to steal Johnson out from under Koscheck.
In Season 12, Team Koscheck came in riding high on their first win after three consecutive losses and having finally gotten under GSP's skin by taunting the losing Spencer Paige. With match-making privilege, they match their #1 pick Marc Stevens against GSP's #6 Cody McKenzie, who is known for his "McKenzietine", a modified guillotine choke that negates the usual escape method of passing to side control. Come fight night, Stevens follows his wrestler's instincts and almost immediately dives head first into a McKenzietine, and reacts by shifting to side control. Stevens is unconcious sixteen seconds into the fight. While GSP tells his team to be respectful in victory, Team Koscheck is left in shell-shocked silence until a glassy-eyed Nam Phan simply says, "Wow." In the second figt of the episode, Jonathan Brookins (whose claim to fame thus far was then-WEC-featherweight-champion Jose Aldo taking more than two rounds to defeat him) comes out and, in less than a minute, lateral throws the big-talking judoka Sevak Magakian, jumps on his back and rear-naked chokes him, putting the score at 5-1 for Team GSP.
Crowning Moment of Heartwarming: Upon his victory, season 11 winner Court McGee fought back Manly Tears. (McGee had been a heroin addict who turned his life around in 2006 by getting clean.) Also, McGee gave his son the middle name Charles, after his TUF coach Chuck Liddell.
The Scrappy: Now and forever, Josh Koscheck. He amazingly manages to come off worse as a coach in Season 12 than he did as a fighter in Season 1, since he goes from merely "dumb, immature jock" to "dumb, gullible, immature jock who turns half of his team into dumb, immature jocks that lose badly and are poor winners".
TUF Brasil also had a share of fighters who were desliked. Pepey (arrogant) and Mutante (always protected by Vitor Belfort) from season 1 and Viscardi (disrespectful towards Minotauro) and Juliano Ninja (arrogant) from season 2 are good examples.
"Stop Having Fun" Guys: Matt Hughes, who so detests flashy moves and such, that he cut a promo calling out Rashad Evans for showboating during a fight in Season 2.
Tear Jerker: After losing her fight, Roxanne Modaferri is her usual upbeat self until she is alone; only then does she completely break down.