nostalgia_lj has just totally floored me with a Doctor Who fic. It contains spoilers for something like half of the entire history of the programme, I suspect, but they're vague enough to be mostly harmless even to people wary of spoilers. It also would appear to require the reader to have a lot of background knowledge about the show, but I found it worked just fine without the background knowledge.
This is, quite possibly, the most perfect Who fic I've read. It made me go '.... guh.... ' and *wibble*. Words fail me.
Read it!