Another pro tip: if you cool down the egg immediately after boiling, it will shrink and be easier to peel even latter when it's cold.
Another another pro tip: by making a small hole on the more rounded side where the air pocket sits, you can generally make hard boiled eggs easier to peel and look better without the strange dimple on that side. The air inside the pocket expands during the cooking process and builds up internal pressure, which may cause the egg to crack mid-boiling; this also causes the membrane to stick more strongly to the boiled egg.
Not really a pro tip: If you don't mind being the weirdo on the dining table, blowing air into the gap between the shell membrane and the egg itself will work too, with the same principle as the running water trick: by introducing foreign material into the vacuum layer between the membrane and the boiled egg you will pry them apart.
Another another pro tip: by making a small hole on the more rounded side where the air pocket sits, you can generally make hard boiled eggs easier to peel and look better without the strange dimple on that side. The air inside the pocket expands during the cooking process and builds up internal pressure, which may cause the egg to crack mid-boiling; this also causes the membrane to stick more strongly to the boiled egg.
Some egg cookers include a needle attached to a base or the measuring cup for this exact purpose. I have one myself.