Can any one help me find some fanfictions?

SPOILER ALERT somewhat I'm searching for a fanfiction where Sakura for some reason joins and or is taken by the Akatsuki. I think she may be a family member of Pein or something. Well she goes back and teams up with the people in Konoha for something again I'm not sure why. I think that in this story Tobi is Madara in disguise and he freaks out Sakura. I'm not sure if it is label as any paing but Sakura am have ended up with Tobi. The other one all I remember is that Team 7 ( Sakura, Naruto, and Sasuke ) go back in time and save Obito from dying.