If we're truly talking about actually rocking the football world, no single win would do it. Not even over Bama.
But a huge, lopsided win would. Like 50-13 over Bama, or 42-0 over Georgia.
For those who said Vandy, or Florida, or West Virginia ... I don't think us beating any of those teams would rock the football world. They would be very pleasant outcomes for sure, but the football world isn't going to stop, stare, and say 'whoa!'
As for the most likely thing we could do that would rock the football world (none of these things are likely, but most likely among a bunch of things that aren't), that would probably be us winning the SEC East.
It's a fun question. Fits right in there with Bold Predictions.