I so relate to that out of body experience. My story is different though -- 10 years ago, I was driving along the SF-LA scenic route (I forget its name). I'd rarely driven in US at that time and was brand new to the country. Suddenly I felt like I knew the route. I'd seen these underpasses before, surely? It was so surreal. I could even predict some road feature that was going to show up next.

Turns out the game Roadrash that I played as a kid had that route :)