Idea: Tom Marvolo Riddle becomes immortal as a teenager in a universe where Dumbledore is an evil and manipulative old bastard who'd created Voldemort and is using Harry.
Tom Marvolo Riddle aged fifteen and three quarters cursed Albus Dumbledore for the who knows how manyth time as he regained consciousness and gasped for air that wasn't there. If Dumbledore hadn't decided that turning a small orphan with serious issues into competition for and therefore a distraction to his former lover Grindlewald was a good idea, he wouldn't be in this mess. He knew he should have run off and joined the Army when whatever control spell that bastard had put on him wore off a couple days earlier than expected instead of coming back here. But nooo, he had to come back to Hogwarts, be put back under that stupid spell that somehow got around the potions he had been put on by the healer after that incident during his first year to er... stabilize him, and find the fucking Chamber of Secrets.
If he ever got out of this goddamn snake, he was going to make everyone pay, starting with Dumbledore.
That bastard's goat buggering brother was right, no matter how nice he seemed at first, Albus Dumbledore was a total fucking asshole.
Tom Marvolo Riddle aged fifteen and three quarters died for the sixty seventh time that week and had another week and a half to go before he reached the other end of the starving basilisk who had swallowed him. It was probably the worst place ever to discover that one is actually immortal.
BEING AN EXCERPT FROM THE PRIVATE JOURNAL OF WATCHER EDWARD HITCHENS:
It seems that poor Tom's gotten himself free from his master again. While being stabbed to death in a dark corner in Knockturn Alley would be a bad thing for most people, it is a fortunate occurence for my former classmate and first assignment out of the Academy. Soon after getting up, he gave his notice at Borgin and Burke's and walked to the nearest recruiting office. It seems that I am going to be joining the Army, if Tom can find a way to avoid his master long enough to be shipped off to basic training that is. Father is going to be so proud when he finds out. I however am not so happy as there is a chance that I will be sent off to war in Korea.
The muggle military is a rather strange career choice for the end of the Slytherin line. It probably has something to do with his upbringing in the muggle world. Had St. Mungo's allowed the birth of Immortals on its premises and not turned Merope Riddle away, I would quite likely not be in the position I'm in right now. How the wizarding world had gone from believing that abandoning Immortals where they would be found and raised by muggles was a mercy as ninety five to ninety six percent of them would be unable to perform magic and all would be unable to create heirs to continue their lines, and would be forced to watch as several generations of their families grew old and died to vewing them as they viewed every other "Lesser magical creature" and denying them basic services such as medical care, I don't know.
THE FOLLOWING BEING AN EXCERPT FROM THE JOURNAL OF WATCHER ALEXANDER THOMPKINS:
Being the third watcher for the Immortal named Tom Marvolo Riddle and known to the world as Voldemort thanks to the efforts of an elderly wizard that had attempted to use him as a tool - first intending to use him as a distraction against the Dark Lord Grindlewald, and later after Grindlewald's defeat as a means to push an agenda through the Wizengamut either by the death or incapacitation of his opponents through inprisonment or otherwise - I was not there for his military service following his departure from Borgin and Burkes or his later adventures before his recapture by Dumbledore and subsequent "Rise" as "Voldemort" during the first war, nor was I there for the events on that infamous Halloween night in 1981. I was however there during the evening of "Voldemort's" infamous ressurrection, which Tom spent having coffee at a Starbucks in Seattle. I was also there last night for the final battle with "Voldemort" which Tom spent in a pub in Edinburgh before later going home with a rather attractive red head.
Any who read this after I am gone will ask, how is this possible? The answer is that there was a time from the late Sixties through 1981 that Tom had actually been Voldemort, but he quit on that Halloween when a killing curse rebounded off of a special shield created by Lily Evans Potter - Harry Potter's scar is the final sigil that was needed to create the shield according to my predecessor - and hit him, killing him, once again breaking the hold Dumbledore had on him and returning any memories Dumbledore had seen fit to remove. After faking his death by transfiguing a teddy bear into a set of charred robes and blasting the nursery to kingdom come after properly shielding young Harry Potter from the debris, he ran for it. Since when Tom is (mostly) sane, he believes Divination to be total bullshit, he felt no need to make any further attempts on the young Potter's life. After fleeing the Potter home, he stayed on the run until the summer of 1992 when he found himself infiltrating Hogwarts under the guise of a Sixth-year transfer student from the Philedelphia School For Young Wizards, Est. 1842 in order to retrieve an experimental dark artefact that he had created while under Dumbledore's influence. After Harry Potter saved the day, he escaped Dumbledore's grasp yet again and has been wandering the world ever since. The thing that everyone calls Voldemort was Dumbledore's creation, sustained after his death by the blood stolen from the Boy-Who-Lived.
Being a wizard as all Tom's watchers have been, there had been a time when I had actually swallowed the whole "Lord Voldemort" hype, but that was before I became a Watcher and learned the sad truth. Tom Riddle was a boy who had suffered through a miserable childhood and as a result became exceedingly troubled. That, coupled with a genetic tendency towards violence and severe mental illness had been a rather unfortunate combination. Fortunately for him, the wizarding world had a wide variety of potions to deal with mental problems (though few used them due to the social stigma that was attached when it is discovered or it is rumored that an individual used them). He probably would have achieved a normal life thanks to the secret potions regimen he had been started on in his first year after he had set fire to one of his dorm mates using muggle methods - namely a cigarette lighter he'd filched from someone at the orphanage in which he had resided - had Albus Dumbledore not gotten his hooks into him.
Had I not been there for the infamous "Chamber of Secrets" incident I would have been completely shocked by the event that had taken place this morning. Albus Dumbledore's sacrificial lamb who rather ironically outlived the man who had planned to use the boy's death in a plot to gain more power while still appearing to be completely benign before something done to one of Tom's false Horcruxes by a well meaning Severus Snape caused his plans to derail had turned out to be a pre-Immortal, and thanks to the events of last night during the battle with the homunculus that had been calling itself Voldemort the last three years or so is now Immortal. Had all memories not been returned to an Immortal upon "death", the events of this morning would have gone quite differently. But, all of the Potter boy's memories were returned, and when Tom came to survey the damage that was done to the home of his infamous ancestor, the place that had once been both first home and hell for him, he left with a student. He left with Harry James Potter the Boy-Who-Lived, the Chosen One, the "Defeater-of-Voldemort".
Knowing what Tom has been getting up to these last few years, I fear that Harry will learn little more than how to get a beer while looking underage because he was too drunk to or couldn't be bothered to apply a glamour, where the "best" beer is at, how to score, the least painful ways to kill oneself in order to get rid of an STD, and how to "Get the fuck out of Dodge". Tom has never really applied himself when it comes to "The Game" and would rather run than face another Immortal. In the twelve years that I have followed him, I have not once seen him take a head. It would appear that the name Voldemort is quite apt considering it could mean "Flees from death" which is something Tom does better than almost any other Immortal I have heard of.