What are some examples of data sets with high(ish) r with high p (low confidence), and low p (high confidence) with low r? I guess it would be a very tall, "sh

What are some examples of data sets with high(ish) r with high p (low confidence), and low p (high confidence) with low r? I guess it would be a very tall, "sharp cornered" parallelogram of data points (clear slope at the average, but high error variation), vs a very short, wide rectangle? That would be a cool explorable demo.