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definitely (Probably)
After two and a half years of solid writing, author John McCrae has just finished Worm, a web serial containing 1.6 million words. That's about as long as the Bible...plus all seven Harry Potter books.
Trust me, every single one of those words is worth reading. The series has a five star rating with overwhelmingly positive reviews on the Web Fiction Guide and has been kept firmly on the #1 position for the past year and a half(maybe longer, but that's when I started reading) over at Top Web Fiction. It has a Facebook page, Subreddit, Wiki, TV Tropes listing(HUGE SPOILERS), IRC, and multiple different forum threads.
Please don't let the title or description turn you off - the first chapter makes it seem like an angsty teen drama, and I almost stopped reading afterwards. Persevere past the first Arc before passing judgement, because that's where the story really picks up. I don't want to spoil anything, but if you read all the way up to Arc Eight it will blow your pants off(In a good way).
That's not to say the beginning isn't written well; it's superb. But the later chapters are the literary equivalent of...whatever the coolest thing you can imagine happens to be, times a billion, while surfing through lava and punching Godzilla in the face. And it just keeps getting better as you go on.
Be warned though, this is NOT one of those stories where you can skip to the middle/look at one of the later chapters to see if it's worth reading. There are HUGE plot shifts between each arcs, and every chapter introduces new elements to the story. Don't let your curiosity spoil this for you, because that would be a travesty.
...Anyways, what are you waiting for? Why are you still here when you could be reading?! GO!