I remember a story where a demon tortures post-hell Dean and Dean is appalled of her (?) shoddy work. He re-educates the demon how torture should be done because that is something he definitely knows. I don't have the link anymore but perhaps somebody recognizes it?

I got it! http://honeylocusttree.livejournal.com/45382.html

Edited 2012-04-11 10:34 am (UTC)

Thanks for the link, I wanted to re-read that anyway

For number three, try honeylocustree's Amateur Night at the Apollo http://honeylocusttree.livejournal.com/45382.html It's pretty awesome!

Kikkimax wrote a two part Criminal Minds crossover that sort of covers what you want. 'Defect' takes place during Dean's last few days before his time comes up, in the hands of Hotch, Gideon, and their team. I don't know about the forty years but 'Hell, and Back' deals with Dean's severe case of PTSD and how Sam and Bobby turn to the profiler team to help him through it. It's at Kikki's site (www.fanfic.ortherplaces.net) and Supernatural crossovers (community.livejournal.com/sn_crossovers).

There's a few very dark and graphic Dean/Alastair called "Pet" I really liked http://nevtelen.livejournal.com/983.html That user also has a couple other Dean/Alastair fics

The firestarter (http://archiveofourown.org/works/467477): Set during On the Head of a Pin. While he waits for Dean, Alastair reminisces on what brought them together. Those forty years? Were delicious.
Images of Broken Light (http://archiveofourown.org/works/85148): Dean may have been brought back from Hell, but Hell followed after him. Faced with losing Sam to Ruby and surrounded by lies, Dean finds the only one telling him the truth is the demon that destroyed him. Slowly Dean finds himself being sucked back into Alistair's embrace.
These bones of mine (http://archiveofourown.org/works/5796): Torture is really just a matter of perspective.
Sense Memory (http://archiveofourown.org/works/161058): This is not hell, and Alistair is not some random soul to be cowed, or disturbed, by a sharp knife and string of graphic threats.
Where Your Love Begins (http://archiveofourown.org/works/502728): There are much sharper weapons than knives. (Alastair/Dean is really is backround thing, but meh, whatever)
In This Hollow Valley (http://xxamlaxx.livejournal.com/254301.html): AU beginning after No Rest For the Wicked. Dean wakes up on the rack to an eternity of torture at Alastair's hands. Meanwhile, Castiel and several of his brothers embark on a mission to rescue Dean from Hell before he can give in and break the first seal. After forty years of fighting, Castiel reaches Dean, only to find that the righteous man is no longer righteous. Castiel resurrects Dean so that he can play his part in the coming Apocalypse. Once back on the surface, Dean has trouble adjusting to life the way everyone (himself included) expects him to. Hell changed him, and he's not so sure if he can or wants to change back.
Midnight Meetings (http://archiveofourown.org/works/5793): Dean starts to disappear at night and Sam follows