Reading a paper emphasising diffs between two groups (n=40k each) on a cognitive task. They had near identical mean accuracy 75.2 vs 75.3, Cohen's d was <.2 and the p value was 0.000000006. Remember kids, bigger often just makes the trivial significant which is never better. I should also add that the task was pretty weak to begin with. I worry that the push towards online testing and large sample sizes is going to lead to a lot of meaningless, but statistically significant, cog. neuro for a while. Just as underpowered samples did.