The Tranquil Fury he exhibits as he cuts off Sidious is also pretty awesome, because you know that for the first time in six movies, Yoda is pissed.
"If so powerful you are, why leave?"
Even better when viewed as part of the series. Those who know Palpatine know that he is a man who is absolutely in control of everything around him. He never panics, always thinks about a dozen steps ahead and never acts intimidated or worried. And he is running scared for his life from someone he had taunted only moments ago. For the first time in the series, he has met someone he cannot intimidate or bully, someone who will never be swayed by his words or fall under his spell. He has encountered someone who can destroy him and is damn sure going to try.
The whole slaughter of the council, without Anakin making a sound, is one of the best scenes in the movie, especially when Nute Gunray not only gets what's coming to him but is brutally cut down mid-whiny plea for mercy.
Equally satisfying is the fantastic contempt in Palpatine's voice when he commands Anakin, newly-minted as Darth Vader to "WIPE OUT. VICEROY. GUNRAY. And the other separatist leaders." It's a great reminder to the audience that these sniveling characters are still hanging around and haven't paid for any of their crimes yet. Admit it, you were rooting for Anakin in that scene.
The novelization's version of the scene where Vader wakes up on the slab is wonderfully nightmarish. Here, take a Vader Breath:
This is how it feels to be Anakin Skywalker, forever: You can hear yourself breathing. It comes hard, and harsh, and it scrapes nerves already raw, but you cannot stop it. You can never stop it. You cannot even slow it down. You don't even have lungs anymore. Mechanisms hardwired into your chest breathe for you. They will pump oxygen into your bloodstream. Forever.
Even with the Big "NO!", the scene where Vader awakens is actually quite chilling.
Obi-Wan's triumph over General Grievous is probably the character's single most badass moment in the film, and he even gets a Bond One-Liner: "So uncivilized."
Better yet, at the start he is alone, has almost no weapons and no guarantee of success. And he fights anyway without showing any fear. At that moment, Alec Guinness is no longer his goal. Ewan McGregor has just proven himself a worthy successor to Harrison Ford.
The opening. We see a Republic battleship floating over Coruscant, then the pair of starfighters Obi-Wan and Anakin are in fly over it, skimming the dorsal surface before executing a perfectly synchronized barrel roll... right into a massive space battle.
Hell the entirety of the Battle of Coruscant counts as one, we see practically over 100 Republic and Sepratist battle cruisers scattered around above the orbit of Coruscant going at it and most likely about a couple hundred to maybe thousand clone and droid star fighters chasing each other around in one large massive space dogfight. And to top it all off Anikan and Obi Wan flew straight through all of that without getting shot down, managed to finally kill Count Dooku, got the chancellor out alive, and successfully landed half a battle cruiser and came out with barely a scratch. As Obi-Wan says when they touch down on Coruscant, "Another happy landing".
Artoo destroying the buzz droid that landed on Anakin's fighter, with some advice from Obi-Wan. Even better in the novelization where Artoo busts out every tool his on on his person and leaves the buzz droid in pieces.
All of Anakin's piloting stunts, but the crowning one is his successful landing of the broken-off bow of the Invisible Hand. Quoth the novelization: "This is, put simply, impossible. He's going to do it anyway."
The novelization had another one during its introduction, when describing Obi-Wan and Anakin making their appearance.
There's no post-production speeding-up of the fast-paced climactic melee between Obi-Wan and Anakin in the end; Ewan McGregor and Hayden Christiansen got so skilled from years of lightsaber training and filming, both from this film and Attack of the Clones, that they could indeed duel at the pace you see on film.
R2-D2 takes down TWO Super Battle Droids. With just his wits, an oil slick, and a pair of rockets. I want him on my side.
Grievous escaping by smashing a window and exposing the entire room to the vacuum of space. As smug as he may be, that takes balls.
Palpatine versus Mace Windu... and Mace wins.
A combination of Awesome and Tear Jerker: Darth Vader taking his first breath.
Obi-Wan and Anakin's fighting styles. They've been at war for a good three years now, and know exactly how to kill the highest amount of enemies with the least amount of effort. Back in the first two prequels, being surrounded by battle droids was a serious problem. Now, it's a minor inconvenience.