Three Specific fics:
a) Dean was previously cursed by a witch to become a panther but it missed hitting him directly; Sam explains this to someone by using a bag of flour or something, saying that even though it didn't hit you, some of the flour still managed to get onto you. Sam and Dean were hunting this ghoul that infects animals to get more food and the two of them split up to cover more ground and to kill the infected animals more quickly to prevent them from infecting other animals. Dean goes missing and Sam tries to find him only to find a panther (which is Dean). Dean thought that like last time that it would only be a couple of days before the curse lets up but he was still stuck as a panther. Sam and Dean travel to a person who could help them turn Dean back into human.
I think that the fic had a great amount of detail when it came to weapons.
Found in the comments below!

b) Dean gets hit by a curse intended for Sam because the witch and Robo!Sam got intimate one time and she wanted to have another round, so she threw a curse that made the soul leave the body. However when Dean was hit by it, his soul did leave his body but his body went into a coma like state. So later at the motel room, Sam calls Cas for help. Castiel sees Dean's soul (which looks like a young boy) in the room and tells Sam. Castiel keeps Dean's soul company until he returns to his body.

c) Sam and Dean get turned into Gargoyles because John went after a nest(?) of them. John leaves them at a hunter friend's house because he could not handle the idea of his boys as supernatural beings that equate to them being evil.

General fics:
1) Fics where Dean is cursed into a dog? I guess werewolves/wolves count too.
2) Are there any other Gargoyle fics out there?
3) Fics where Dean mentally becomes like the supernatural being he was changed into? Or where he enjoys what he has become? (A great example is Dragon Emperor by Blonde Empress.) 
4) where Dean is diagnosed with cancer or some other life threatening illness. 

Fics can be gen or slash.
Just give me a heads up if it is Wincest. 
Destiel is a bonus!