Indestructible:

The Doctor paused in mid-meltdown. "I'll just nip down to the TARDIS for a bit, won't be gone long," he threw over his shoulder as he sprinted away.

Barely a second later the TARDIS materialized and a handsome man in a vintage coat stumbled out, followed by the Doctor. He looked back towards the Doctor and said, "This better be good, I was about to score with a pair of Vendaxian twins."

The Doctor replied, "It won't take long, Jack. Just step into the booth, shut the door and press the big, red button.

Wilf watched with horror as the stranger complied and promptly died from radiation poisoning.

The Doctor gave Wilf a cheery grin and said, "No worries, the Captain will be as right as rain in a few minutes. Good thing I remembered I have a time machine and an indestructible friend."

It's Right In Front Of Your Nose

The Doctor stepped out of the booth. He could feel the radiation beginning to damage his body. He steeled himself for the inevitable. Suddenly, a thought occurred to him. The Immortality Gate was designed to heal entire planets. Surely it could fix a simple case of radiation sickness for one man.

It worked.

Why Didn't I Think Of That?

Just as the Doctor was about to step into the booth, Wilf said, "Um, Doctor, you just said that you can't let me out because aiming the sonic screwdriver at this booth will cause it to flood with radiation."

The Doctor nodded.

Wilf continued, "So aim it at the other one!"

The Doctor looked gob smacked for a couple of seconds, then complied.

Wilf stepped out of the booth muttering about geniuses.

Re-Run

The Doctor, reeling from radiation sickness, made his way to the TARDIS. This body, this face, is far too pretty to die, he thought desperately. There must be a solution, think, man, think!

An idea struck him. It worked once before, he thought, as he cut off a lock of hair. He then pulled the same partial regeneration stunt that he pulled last year. A few minutes later a newly healed Doctor faced yet another clone.

Now, what to do with him, the Doctor thought. "How about I send you on a nice, long visit to Captain Jack?" he said. "I'm sure he'd be more than happy to give you a helping hand."

The clone, having a pretty good idea what Jack would consider a 'helping hand', emitted a horrified squeak.

The Doctor sighed. Mentally, he ran down a list of possible homes. Sarah Jane, no, she has enough on her plate dealing with Luke. Tegan is still angry at me. Mel, no, I couldn't do that to him. The Brigadier is in his eighties, Joan Redfern got married, Ace is still angry at me. Nyssa lives in a leper colony, and The Master is probably in California starting a new religion.

Inspiration struck. I know I'll give him to Martha for a birthday present. She's been pretty depressed since Milligan dumped her, and in her vulnerable state, she could end up married to some idiot on the rebound. Turning back to the clone, he said, "I've got just the solution. H'm, I'll have to find you something to wear."

The sound of the TARDIS materializing filled Martha's home. Great, she thought, just what I need. The TARDIS door opened and the Doctor, as if propelled by an unseen force, (or maybe a Converse shod foot) tumbled out into her living room. For some bizarre reason, he was wearing a truly hideous Edwardian style coat in psychedelic colors, a red velvet cape, a porkpie hat and an extremely long, multicolored knit scarf. Before she could say anything, the TARDIS disappeared.

Not That I'm Shallow

Just as the Doctor was about to step into the booth Jack appeared. Before the Doctor could react, Jack had sealed himself in and activated the controls. The Doctor could feel the timeline twisting itself into a new shape.

Later, after Jack had returned to life, the Doctor said, "What the devil did you do that for? I would have regenerated."

Jack gave him a roguish smile and replied, "Doc, I did what I had to do."

The Doctor, still angry, snapped, "You stupid ape, you could have created a universe destroying paradox! And what do you mean, what I turned into? I'll have you know, my regenerations are always in the best of taste."

Jack snorted. "Doc, I've seen the TARDIS wardrobe. A cricket jacket, velvet capes, 40 foot scarves, and that coat! What did you do, steal it from the touring company of Joseph And His Amazing Technicolor Dreamcoat?"

The Doctor opened his mouth to speak, and then closed it. There was no defending that particular outfit.

Jack continued. "Doc, once I saw that melon-headed dweeb in his bow tie, I knew I had to do something to save that pretty face of yours, no matter what the risk."

The Doctor stared at Jack in astonishment. "Do you mean to say you re-wrote the timelines simply because you didn't find my next incarnation shaggable?"

Jack shrugged, gave the Doctor his most charming smile and said, "Well, yeah. Don't you know me by now?"