stories are in PDF format, so you'll need Acrobat to read them):
"Clean Slate" by M. Fae Glasgow: Avon gets amnesia, in a story that proves even the most cliched premise can be used to excellent effect by a truly skilled writer. Notable here is the fact that Avon and Blake's sexual relationship (pre-amnesia) is really quite dysfunctional. (I love the way the amnesiac Avon keeps asking people if he and Blake are lovers, and nobody seems to know quite how to answer him... least of all Blake.)
"Revolution" by M. Fae Glasgow (aka "Cally Donia"): Avon and Blake discussing, sex, love, and revolution, not necesarily in that order. Contains very explict and decidedly non-romantic sex, as well as complexities of many and varied sorts. (Also contains lines from the Beatles song used as dialog, which is something that would usually have me running away screaming, but M. Fae manages to get away with it, bless her twisted little heart.)
Actually, M. Fae Glasgow (who writes under that name and various other transparent pseduonyms) is another writer who frequently does an excellent job at capturing the complexities in slash relationships. Her stories tend to be very dark, though, and frequently involve various potentially squicky sex-and-violence things. *Definitely* not to everyone's tastes.
There you go. Some examples, anyway. (Additional disclaimer: it's been quite a while since I read some of these stories, so I may not be remembering the details of all of them correctly.)