Dust by knifeedgefic
http://www.livejournal.com/tools/memories.bml?user=knifeedgefic&keyword=DUST&filter=all
http://www.fanfiction.net/s/6958651/1/DUST
http://www.bloodshedverse.com/stories.php?go=chapters&no=12728
WIP, 31 chapters, PG so far, NC-17 later. Alternate season 4. Buffy wakes in a Sunnydale that went utterly wrong... Everybody's asleep; the phones are dead; and there is no way out of the town. Buffy's only hope is a certain vampire who managed to stay awake and who was persistent enough to wake her up. Intriguing premise, genre storytelling par excellence, witty dialogues, funny insights into Buffy's and Spike's minds, overall creepy atmosphere -- the story's vitality and finesse make "Dust" one of the most exciting and gripping stories of the year.
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There already is a post by snickfic dedicated to long Spuffy fics. She has collected five magnificent stories there, and I regard this post as a continuation of her work.

Where Pies Go When They Die by ghostyouknow27
http://ghostyouknow27.livejournal.com/tag/where%20pies%20go%20when%20they%20die
R. Completed. ~ 17,500 words. Post-series. Spike has landed in a special Hell, courtesy of Wolfram & Hart. Buffy's rescue mission leads her... into a diner from Hell. Deliciously cracktastic tale in Lewis Carroll style with shadows of Tim Burton and Chris Nolan lurking at the corners. Inventive plot, powerful, well-crafted concept, great timing and sense of details - each of them works for a bigger plan. HeavenHell is very unusual - funny and creepy at the same time; Buffy's speech patterns ("What the pie?") as well as her reaction to SPN-skewed reality are priceless.
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Joss provided us with countless ploys to develop the universe he created: alternate dimensions, slayer dreams and memories, not to mention good old sci-fi technologies and, last but not least, characters worth exploring. Here are 5 stories based on unusual plot bunnies.

Nothing Ventured by shapinglight
One-shot, NC-17, between Hell Bells and Seeing Red on BtVS and post-Couplet on AtS. Spike visits Angel in LA and talks with him about Buffy without naming her. Angel thinks they're talking about Dru and gives him some advices... Terrific idea and masterful execution: sharp dialogues, minimalist descriptions, spiced with lethal irony. A character-study-cum-tearjerker-par-excellence.
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