Agents of S.H.I.E.L.D.: Grant Ward. He's recruited due to his stellar field record, and is usually the one who does the most fighting.
Angel: Gunn and Connor. Gunn tended to get called "the muscle" a lot, and the fear that this meant dumb muscle was a big part of his character arc. Connor was something of a subverted Big Guy, his slight, boyish appearance contrasting with his incredible strength and ferocity.
The Aquabats! Super Show!: Crash McLarson most resembles a Class 2. His special power is shifting into super size heights, sometimes triggered by his emotions.
Blake's 7: Gan from the first season is an interesting variation on the trope; he would count as a classic Class 2 by dint of his backstory, having sought out and killed his wife's murderer -with his bare hands according to Fanon- but he was subsequently implanted with a 'limiter chip' that restricts his aggression. Also a mild subversion on account of being the Big Guy in a series where Gareth Thomas is playing the Hero. Though, to be fair, he is a pretty nice guy anyway (At least compared to some of the others on the show. * coughAvoncough!* )
Buffy the Vampire Slayer: Willow, but she's an interesting case as she can fit as The Lancer, The Smart Guy, and The Chick depending on what's needed, and who is around. However, she is repeatedly stated to be the heaviest hitter in the group once she properly develops her magic powers, even exceeding Buffy herself.
Spike was once described by Buffy herself as the "strongest warrior they have", and thus he is often used as the meat shield by the scoobies. It helps that he's a Blood Knight who loves fighting and only really joined because he wanted to beat stuff up and his Restraining Bolt stopped him from doing that without help from the scoobies. He's also been shown to be quite cunning on occasion, but most of that is eclipsed by his Butt Monkey status.
Leverage: Eliot Spencer from is a perfect example of this trope, and they make no efforts to hide it either. His label in the show is "The Hitter" (sometimes the The Retrieval Specialist but it all adds up to the same thing), and he handles both the heavy lifting and the violence, to the point where he verges on The Brute on occasion. Interestingly, he is the shortest of the main guys, and shorter than the girls (when in they're in heels).
Ninjor from the third season is a Class 2 Big Guy.
Katie from Time Force, who has Super Strength even when she's not morphed thanks to 31st century genetic augmentation. Flynn McAllister from RPM is a Class 2.
Adam Park is considered by many to be The Big Guy during his seasons, due to his quietness and all around badassitude. In fact in his Power Rangers Zeo article, he's listed as The Big Guy.
Other Power Rangers Big Guys include Kai Chen (Blue Galaxy Ranger), Chad Lee (Blue Lightspeed Ranger), Danny Delgado (Black Bison Ranger), Dustin Brooks (Yellow Wind Ranger), Tommy Oliver (Black Dino Ranger), and Kevin (Blue Samurai Ranger).
Misfits: Kelly is far more violent and confrontational than any of the males in the group, and was the only one to take decisive action when they were attacked by their Ax-Crazy probation worker, killing him single-handedly by knocking him to the floor and kicking his head in, although he was about twice her size. She isn't physically large (she's about average height and build) or notably "butch", and does actually have quite a caring and sensitive personality. But she can often seem imposing due to her anger management issues and will blithely maul anyone who insults her - in fact, due to her power of telepathy, she will occasionally attack people just for thinking something that offends her in some way.
NCIS: For a twist, it's "Big Gal", with Caitlin Todd the former Secret Service agent, and then currently Ziva David, the former Mossad operative. Both are/were the designated asskickers (though the others in the Five-Man Band aren't slouches, either).
Noah's Arc: Alex is a class 4, being outspoken, boisterous and dramatic. Though kind, he is the most aggressive and confrontational of the group when threatened. He is also an Emotional Bruiser.
Ronon Dex is a Class 1. His nickname is even "Chewie".
One of the best scenes is Teal'c (who is, at this point, over 100 years old) and Ronon going at each other, while everyone else is making bets. Too bad Carter had to stop the fight, which at that point had been going on for over forty minutes!
Stargate SG-1: Teal'c is a Class 2 with occasional Class 1 leanings.
Star Trek: Enterprise: Malcolm Reed is one of those rare Class 5 big guys. As the ship's tactical officer, he's not only the go-to guy for beating people up and blowing stuff up, but also for coming up with innovative new ways of doing both of those things. He uses his brains and technical know-how almost as often as his phase pistol, but he's still an extremely capable combatant, as shown when he engages in a no-holds-barred brawl with the leader of the MACOs.
Dean even if he doesn't look the part. He's tiny compared to Sam and looks girly and vulnerable but is an incredibly brutal fighter.
Castiel, as the strongest ally the Winchesters have, is often called upon to do the heavy lifting when the Winchesters come across monsters too strong for them to beat (this is made apparent in season 5 where Castiel mows down angels by the truckload in contrast to the boys who can barely defeat one). He's also the shortest of the main characters and is described as a "nerdy angel dude".
The Vampire Diaries: Caroline. She even knocks Damon around like a ragdoll when she gets pissed enough.
The West Wing: Joshua Lyman was the political equivalent of this trope in the Bartlett administration, functioning as the the President's attack dog and enforcer. Lacking subtlety, Josh was a political bludgeon, beating Congressmen, Senators, and Secretaries into line with threats, insults, and even outright blackmail.