In the large-word using and scientific way of language Heimerdinger uses, I would select the word omnipotent to describe his pushing power. Especially when placed in a solo lane Heimerdinger can gimp an opponent incredibly hard, using his towers to efficiently destroy their minion waves followed by them if they don't get out of the way and tower hug. With his huge range on his skillshot, it's easy to land a large portion of damage on any enemy champion's health even when tower hugging, and if they're not around, on the tower itself.

Techmaturgical Repair Bots
There's nothing wrong with group health regen. Let's leave it at that.


H-28G Evolution Turret
What makes Heimer Heimer. Without turrets, he is nothing. With turrets, he is god.


Hextech Micro-Rockets
A nice finisher, and also a good farming move when combined with Level 5 turrets or a Grenade. Note, that contrary to the description, the rockets hit minions.


CH-1 Concussion Grenade
A slow skillshot that stuns and blinds, while doing 300 damage without and +AP boosts. How nice. On a note, your Concussion Grenades can be used to damage towers: a great finishing move if your team has just been beaten and that tower is still alive on 20 HP.


UPGRADE!!!
Great for a lot of things. If your turrets are low, the cooldown is so low (especially with the bonus CDR it gives) generally that you may as well drop it. If an enemy champion is chasing you past your turrets, drop it, so they slow and get a ton more shots in. I've been able to reverse ganks champions like Shaco, Evelynn and Warwick have attempted and managed to get a free kill from it.

Pros

- Does lots of damage late game
- Can Heal Towers
- Can Hold a Lane Alone

Cons

- Targeted in team fights
- Low HP
- Runs Out Of Mana Fast