Keeping this good thread going, the FA Cup ties against Bristol City in 1978, when Bristol City were in the top division. Coming from 2-0 down in the first game away to 4-2 up, followed by 2 late goals from Bristol City to force a 4-4 draw. In the replay we played them off the park winning 3-0, and I seem to remember we also missed 2 penalties. That team was a joy to watch week in and week out.
https://youtu.be/M4dMtzCMkn0