I was expecting this thread to be about the aftermath of a trip to Taco Bell.
Seriously, when I had this exact same problem happen to my Escort, it was the fuel filler tank hose (flexible hose between the metal fuel filler piece and gas tank). With the gas tank level at the appropriate level it's only noticable when takeing a turn. If the hose gets bad enough, gas will spill right out when doing a fill up. It would explain why you aren't seeing or smelling anything in the front of the car or with the hood up. I was smelling gas everywhere but from under the hood, and it was very consusing. The offending bad hose looked like this:
When I say the problem was confusing, it was because mine was at the beginning stages of being bad. If you wait long enough and the hose gets worse, you'll easily notice a gas puddle when filling up the car. I know you stated no MPG problems, but this hose could have just gone bad.
It's easy enough to check.