This is a Sastiel story that the author only had on their LJ, it hadn't been moved over to AO3. Unfortunately their journal was suspended.

Summary: When Sam takes notice of an unusual student in a bar near Stanford, he introduces himself with this question: “If you had the power to do anything, what would you do?” It turns out the answer isn’t as vague as it seems. Sam/Godstiel, time travel.

Does anyone have a copy of this fic?