It's kinda minor, but Gary humiliating the dumb jock, David Burton, in front of the entire school, with the Facebook insults that they were shooting behind his back.
Also, anything that Hicks does with his Alpha power.
Especially defending Gary from the aforementioned dumb jock and four other bullies without getting so much as a scratch, and finishing it off by tripping David Burton with a textbook from fifty feet away. He also took out the coach, which was just icing on the cake. It must also be noted that Hicks didn't technically hit any of them, just subtly redirected their movements so they basically took themselves out.
Shooting the (very, very small) box knife out of a superfast Alpha's hands in "The Quick and the Dead."
Maybe it's not good form to be giving props for an act of evil, but the Brain Washed Hicks in the pilot successfully gunning down a witness, sight unseen, by firing a bullet through an air duct from a rooftop thirty yards away.
Another Hicks moment: with about three seconds of prep time, he manages to save Nina from jumping off of a building. His rescue involves jumping off the building himself, and then catching a hook that he set in motion with a gunshot before jumping.
Gary tracking down Skylar with the help of a very patient cab driver. It may not seem like much, but you have to remember Gary did it pretty much without prompting.
Just about everything Skylar invents results in one of these. She even made modified contact lenses in case Nina tried to mind-control her!
Rosen smashing the super control brain from Bob after obtaining it from Skylar. He spent the entirety of the series up to this point acquiescing to the decisions of those above him... until he finds out that Skylar has a daughter. He rebelliously covers for them, saying that they disappeared, standing up to an armed and angry federal agent and the brunt of his superiors. With the device, he could have given his bosses every Alpha on the planet and gotten praise and adulation galore. But he defiantly chose a clear conscience instead.
Rachel, coming out of nowhere during "Blind Spot" and beaning the invisible Alpha upside the head a few times..
In the same episode, Dr. Kern shows he's a Not-So-Harmless Villain once he's built up enough sonic energy and starts absolutely wrecking the offices, along with anyone who tries to get close to him.
Was it awful that Bill and Cameron were fighting? Yes. But the fight itself was epic.
The break out in the same episode was pretty awesome. Bouncing tranq darts, tearing through guards and super alpha jump kick to a locked door just icing on the cake.
Rosen waking up in a strange place after being unconscious for days, and having the presence of mind to grab nearby chemicals and syringes and kill an Alpha assassin.
"Original Sin" has several:
Hicks' Le Parkour duel with another Alpha who has the same abilities as him. Even if Hicks lost, it was a kickass fight scene.
Gary going completely apeshit on a DoD soldier after finding Anna's body. Also a Tearjerker.
Rosen performing an Engineered Public Confessionon Congress in order to expose the Alpha situation to the general public.
In Gods and Monsters, Parish once more plays the Alpha Team like a violin despite all their efforts to stop him. and he does this without any thugs to protect him, using sheer psychological manipulation and cunning. And then he macgayvers his way out of a prison cell, kills two guards, sneaks out and enters in Jason's mind. Good LORD.
In the same episode, Rosen and Parish have a long-winded verbal version of a Battle in the Center of the Mind, both trying to twist each other's arguments at a ridiculously quick pace to convince a boy, a crowning moment for both of them. And then it becomes Rosen's moment when he makes the battle physical in the mind, subduing Parish and taking a look at a good chunk of his memories.
Before those two, for me, was the teams quick detective work in finding Parish. At first you think it was going to devolve into a hostage situation when Rachel realizes it's not Rosen she's talking to. Nope they (conference) call back, tell them to their face he's not Rosen and everything they've done to cover their tracks. Gary is working to find them because Rachel can tell their indoors and Bill claims they could send a team there in five minutes.
Bill smacking Kimi Malard halfway across the room during "The Devil Will Drag You Under"
In the same episode, Hicks and Scipio have a pretty cool chase scene with some metal at the background, and eventually Hicks manages to crash Scipio's car with the most Crazy Awesome technique of all time literally crashing onto him with his bike, jumping over the car and watching the car lose control. Badass.
Bill and Kat's Fastball Special. Bill uses his Super Strength to toss Kat into the air and have her land behind the guys shooting at them, whereupon she beats the crap out of them and kills one by making another shoot him.
There's even one particularly awesome scene where Rosen and Parish meet in the middle of the station. Both stare at each other, Rosen readies his syringe, but Parish just stares at a golden pocketwatch. Cue a horde of passangers arriving from the train and Parish vanishing in the crowd. He was timing everything.
There's something awesome about the moment Rosen and Parish walk towards each other in the station, minutes away from a world-changing event in the Alpha War, the two greatest minds on each side stare each other down, ready to make their last move as their pawns move in the chessboard.