As already mentioned... The Castle Course is #1 for the courses I have played.
Stanwich, CT - big contours and always rolling fast (just heard they are replacing all 18 this year)
Baltusrol Upper, NJ - they say everything breaks away from the mountain, but when you know which way its going and its still 3-putt city!
(haven't played the lower, but more severe internal contour then WF, QR, Ridgewood, Fenway)
Others stick out: Old Mac, B Trails, and Winged Foot East/Carnoustie (may have been the 2 hardest courses I have ever played from just off the green)