If you accept self recs - Soulless!Sam experiencing subdrop after a scene with Dean
http://citrusjava.livejournal.com/178737.html

Self recs are more than fine and I just wanna say, I read this fic before on tumblr and its actually what made me want to read more about it. Thank you so much for this fic! <3

Aww, thank you!!!!
*blushes a lot*
Since I saw your post I keep trying to think of others, but nothing specific comes to mind....

If you don't mind John &Mary of "In The Beginning," I wrote Finders, Keepers (http://archiveofourown.org/works/512320/chapters/903290). A young girl finds Mary's diaries in her family's motel in Salvation.

If you like AUs but with mature John & Mary, then try clex_monkie89's "Heaven's Aligned Against Us (Sounds Like a Fair Fight) (http://archiveofourown.org/works/230063)"

I haven't read the first one but I did read the second one before. I'll read yours very soon though! Thank you very much.

The two last installments of the By Your Command 'verse (http://archiveofourown.org/series/38957) by Wincesteriffic Kaz, "Into the Light" and "Unexpected Consequences", have sub drop. It's not the main topic of 'Into the Light' but it definitely is there and identified as such. It is the main subject of 'Unexpected Consequences', but it's a 6,000 words fic that supposes one has read the other fics in the 'verse, or at the very least the one before it in the 'verse.
Those are the only fics I've read that have sub drop...

This one eventually focuses on Dean and Destiel, but the first chunk is about John/Mary. Hunter AU.
The World Tree (https://archiveofourown.org/works/374723) by Sorka42
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