Here's something weird: One guy on the internet has made a claim that crime fiction author Raymond Chandler wrote his stories on index cards. The idea was to ensure that something interesting happened on every single card(about every 250 words). The weird thing is, there's only the one guy as far as I can tell making this claim. I don't have a good source that proves Chandler actually used this strategy. But like Neils Bohr said when asked if he believed his lucky horseshoe was actually lucky: “Of course not... But I understand it’s lucky whether you believe in it or not.”
Among the provable users of index cards for writing, Vladimir Nabokov stands out. He wrote entire novels on index cards and sent them away to be typed up. According to him, the advantage is that the writer can take finished cards, or collections of cards, and easily shuffle them to make new configurations. Gaps in the story become opportunities to create or shuffle in more cards. In his own words: “The pattern of the thing precedes the thing. I fill in the gaps of the crossword at any spot I happen to choose. These bits I write on index cards until the novel is done. My schedule is flexible, but I am rather particular about my instruments: lined Bristol cards and well sharpened, not too hard, pencils capped with erasers.”
For those who want to use Chandler's(?) technique, there is a nice fix for those working digitally. Most word processing programs will allow you to change your page size, you can simply squish the page down until it only holds a couple hundred words, and you're off to the races! If you want to use Nabokov's shuffle, however, there's nothing I can recommend that digitally recreates this analog process.
This shuffling process is easiest with cards, but not necessary. To round this out with a truly horrible blunt rotation, William S. Burroughs must be mentioned. His novel Naked Lunch was assembled out of piles of paper and handwritten notes he had written furiously in Tangiers, and forced into a somewhat book-shaped mold by Jack Kerouac. To quote Burroughs: "The Word is divided into units which be all in one piece and should be so taken, but the pieces can be had in any order being tied up back and forth, in and out fore and aft like an innaresting sex arrangement. This book spill off the page in all directions, kaleidoscope of vistas, medley of tunes and street noises, farts and riot yipes and slamming steel shutters of commerce, screams of pain and pathos and screams plain pathic […] Now I, William Seward, will unlock my word horde." More later on the human capacity to squeeze meaning from randomness, but for now... Write with a relentless pace! And while you're at it, remember that in your story, you are chronology's boss. Ultimately it has to do whatever you say.