7th Update:
"At an end, your rule is... and not short enough, it was, I must say." ? Yoda
There appeared a blade the color of life. From the shadow of a black wing, a small weapon, a hold out, an easily concealed backup, a tiny bit of treachery expressing the core of Sith Mastery, slid into a withered hand, and spat a flame colored blade of its own.
When those blades met, it was more than Yoda against Palpatine, more than millennia of Sith against legions of Jedi.
This was the expression of the fundamental conflict of the universe itself.
Light against dark.
Winner take all.
//cut to Mustafar
Obi-Wan knelt beside Padme.
He barely found a pulse.
"Anakin... Anakin, what have you done?!?" - Obi-Wan
"You turned her against me!" - Anakin
Obi-Wan looked at the best friend he had ever had.
"You did that yourself." - Obi-Wan
"I'll give you a chance, Obi-Wan. For old times sake. Walk away." - Anakin
"If only I could." - Obi-Wan
"Go someplace out of the way. Retire. Meditate. That's what you like, isn't it? You don't have to fight for peace anymore. Peace is here! MY Empire IS peace!" - Anakin
"YOUR Empire? It will never have peace. It was founded on treachery and innocent blood." - Obi-Wan
"Don't make me kill you, Obi-Wan." ? Anakin
"If you are not with me, you are against me." - Anakin
"Only Sith deal in absolutes, Anakin. The truth is never black and white." Obi-Wan
He stands, holding up his open hands in a sign of peace.
"Let me take Padme to a med center. She's hurt, Anakin. She needs medical attention." - Obi-Wan
"She stays." ? Anakin
"Anakin!" - Obi-Wan
"You don't get to take her ANYWHERE! You don't get to touch her! She's MINE, do you understand? It's your fault... all of it! You made her betray me!" - Anakin
"Anakin..." - Obi-Wan
Anakin drew his lightsaber.
Obi-Wan drew his own lightsaber.
"Then I will do what I must." - Obi-Wan
"You'll try." - Anakin
Anakin leapt toward Obi-Wan, and Obi-Wan jumped to meet him in the air. As the blades crossed, the volcano aboved echoed with a shot of fire.
//cut to 3PO
3PO looked cautiously through the hatch of Padme's skiff. There's a goofy paragraph about things 3PO would rather be doing... it was pretty funny.
He walked down the landing ramp.
He didn't really know what was going on, other than hearing that Padme was hurt.
He couldn't find Padme.
He heard R2 in the distance. It translated to "Don't worry, you'll be alright."
"Artoo? Artoo, are you out here?" - 3PO
Artoo was pulling Padme across the ground toward the ship (he tangled his maniupulor arm in his clothing, which was what was pulling her).
"Artoo, stop that this instant! You'll damage her!" - 3PO
"What exactly do you suggest?" - R2 (I love how Stover translated R2...)
"Well... alright... we'll do it together." - 3PO
//cut to Coruscant.
(Just a quick summary.)
There came a turning point in the light versus dark.
The battle shifted from the holding office to the podium.
It began to raise, over 100 meters up... it became the focal point of the arena... had anyone been in it to witness this.
The senate pods began flying every which way, crashing into each other in a thunderous roar... almost echoing the cheers for Palpatine that had emanated through the chamber earlier that day.
Yoda's vision finally pieced the darkness that had taken control over the Force.
He saw the truth...
That he was the avatar of light; the Supreme master of the Jedi Order.
The truth...
That he just didn't have it.
Yoda... had never had it.
He had lost before he had started.
He had lost before he was born.
The Sith had grown; had changed; had adapted.
Palpatine was the culmination of the past 1,000 of Sith training, as well as the intensive study the Sith put into Jedi lore itself.
The past 1,000 years of Sith history had been a preparation for this moment.
The Jedi had been training to fight the last war. The wrong war.
The new Sith could not be destroyed with a ligthsaber, or with a touch of the Force.
The more the light side flowed through Yoda, the more the dark side swelled in Palpatine.
The brighter the light, the darker the shadow.
How could one win a war against the dark, when the war had become the weapon of the dark?
Yoda realized this insight held the hopes of the galaxy.
If he were to be destroyed, that hope would die with him.
//cut to Mustafar.
After thousands of hours of lightsaber sparring together, Obi-Wan and Anakin's techniques were almost identical. They knew what the other was going to do before he did it... every time.
Punches and kicks were blocked, all strikes were parried. They knew each other too well.
They then were inside the facility...
Seems like they're using the Force to set off the blasters in the dead people's hands...
Obi-Wan managed to a deflect a few towards Anakin.
Anakin deflected.
And they send the laser beams back and forth at each other until they dissipated into radioactive gas.
"Don't make me destroy you, Obi-Wan." ? Anakin
"You're no match for the power of the dark side." - Anakin
"I've heard that before... but I never thought I'd hear it from you." - Obi-Wan
Anakin Force-pushes Obi-Wan into a wall.
Anakin steps toward him, over dead bodies... and lifts his blade in preparation for the kill.
Obi-Wan had one trick left. One that wouldn't twice.
One that worked on Grievous.
He reached out through the Force, and reversed the electrodriver's on Anakin's mechanical hand.
His fingers sprang open, and his lightsaber flew out.
Obi-Wan reached out with the Force and drew Anakin's lightsaber to him.
"The flaw of power is arrogance." - Obi-Wan
"You hesitate. The flaw of compassion." - Anakin
"It's not compassion, Anakin. It's reverence for life." - Obi-Wan
"It's not compassion, Anakin. It's reverence for life. (new

Even yours. It's respect for the man you were. (sighs) It's regret for the man you should have been." - Obi-Wan
Anakin roared and flew at him.
Anakin used both the Force and his body to slam Obi-Wan into the wall.
He grabbed both of Obi-Wan's wrists an impossibly strong grip.
"I AM SO SICK OF YOUR LECTURES!" - Anakin
Obi-Wan could literally feel his bones bending, readying themselves for the break.
//cut to Coruscant
Palpatine whipped a pod at Yoda, and Yoda leaped half a second too slow. Palpatine unleashed his lightning while Yoda was still in the air, and "the little green freak took it's full power."
(Obviously, this is putting Palpatine's viewpoing into it, while staying in 3rd person.)
Yoda crashed against the podium.
And fell.
Far, far down...
The base of the arena was 100 meters below.
It was littered with shards of metal from the destroyed pods.
As the little green freak fell, the Shadow became, once again, simply Palpatine.
A tired and old man gasping for air.
He was old, but there was nothing wrong with his eyesight.
He scanned the wreckage, but did not see a body.
He used the Force to flip a switch, which sounded countless sirons throughout the building.
He then began lowering his pod towards the base of the rotunda.
Clone troops were already rushing in.
"It was Yoda! Another assassination attempt. Find him, and kill him. If you have to, blow up the building." - Palpatine
The Force sent a warning to Palpatine. Vader was in danger.
He stopped one of the commanders.
"You. Call the shuttle dock and tell them I'm on my way. Have my ship warmed and ready." - Palpatine
Palpatine ran.
//cut to Yoda
Yoda sprinted across the surface accessway below the arena.
He was running faster than any human could.
And was slicing through conduits and doors as he passed.
And filling the way behind him with high voltage cables.
He began stopping occasionally to slice an escape hole in the wall, so that the forces would have to divide up to search each of his possible exits.
Unfortunately, he knew they could afford to. There were thousands of them.
He pulled out his comlink.
The Force whispered coordinates to him, and he said them into the comm.
"Delay not. Closing is the pursuit. Failed, I have. And kill me they will." ? Yoda
By the time Yoda got to the side of the chamber, he was breathing hard, even with the aid of the Force.
He cut through the floor and dropped into a maintence accessway.
He cut through one of the main power circuits for the lights.
He then cut through the wall and dove out into the open. He used his cloak to slow down his fall. He was too small to trigger the defenses.
However, the speeder flying below would get blasted if it deviated from it's path by even one meter.
He used the Force to push himself outward, and landed in the speeder next to Bail Organa.
They shot away into traffic.
"Master Yoda, are you wounded?" - Bail
"Only my pride... only my pride" ? Yoda
//cut to Mustafar.
nakin forced Obi-Wan's arms down, pointing the lightsabers toward the ground.
Obi-Wan let go.
Of everything.
His hopes, his fears, his obligation to the Jedi... his promise to Qui-Gon and his failure with Anakin.
And the lightsabers.
(And the way this thread was going earlier, his bowels too!)
Anakin was taken by surprise, and instinctively let go of one of Obi-Wan's wrists to reach for his blade.
In that instant, Obi-Wan twisted free, grabbed his lightsaber, and swung it against Anakin's with such force that it pushed them both against the wall which Obi-Wan had been standing and cut through it.
He directed another swing against the wall.
And prepared to direct another, which would cut through so that he could jump through the wall.
He did.
Anakin followed, constantly on the attack.
Obi-Wan gave ground, retreating along a narrow balcony.
High above the lava and fire.
Obi-Wan continued to let Anakin drive him back.
Towards the place where Obi-Wan could sense death. A place, he decided, they should reach together.
[lots of cool action]
Anakin cut through a control panel on the balcony.
The shield holding back the lava vanished.
Fire shot all around them.
Obi-Wan backed up to the end of the walkway; the only thing behind him a power conduit no thicker than his arm.
He stopped unto the conduit without hesitation. His balance was flawless as he deflected attack after attack from Anakin.
Then Anakin hopped aboard the conduit too. Their blows came faster than before.
Smoke blocked out the sun.
The only light came from the lava below.
Unlike Yoda vs Sidious, this had nothing to do with Jedi vs Sith, or good vs evil, or light vs dark.
It was simply Anakin against Obi-Wan.
Obi-Wan back flipped to a coupling nexus, and just as Anakin leapt to follow, Obi-Wan back flipped again.
They went on a chase, back and forth, through various levels of conduits and coupling nexuses, collection panels, etc.
They ended up on a collection panel. Obi-Wan ended up on the edge of one, hiding behind it for protection from the lava, while at the same time blocking Anakin's assault both with the Force and with the lightsaber.