Yeah, many for me. A bunch already mentioned, like the uphill with the shallow left-hander at the N'ring (used for one of the license tests in GT4 with a slippery M3), the last corner at Fuji, last corner at Laguna Seca. Also, the first corner after the tunnel at Deep Forest -- can never seem to get the right line there. First corner after the tunnel at Trial Mountain, where you pop over a slight rise, then turn right between the big rocks. Always apex too early, then have to slow down to keep from hitting the wall of rock.
Also, the first corner at Daytona's road course coming off the dogleg. The yellow lines on the left cross the track, and I end up trying to stay right, until I realize that the lines are leading me straight into the wall...
Also at Rome after going down the backstretch, you go over a rise, and at the bottom of the small hill, the track jogs left then back to the right. I jog left, and tag the wall before going back to the right. The AI does it like crazy, there, too.