Harry smiled. Just because of that incident in the vaults and the fact that, due to some enchantment on the Sorting Hat, the wizards had gotten their hands on a certain Goblin made sword again, the Goblins had tried to hold the Wizarding economy hostage. The key word here being "tried".

"Harry! What did you do?!" Hermione screeched as she stood in the middle of an empty bank lobby.

"Just sent the nasty little buggers off to a different world." Harry replied with a grin.

Elsewhere:

Gandalf spoke the Elvish word for "friend" and the secret entrance to the mines of Moria opened. The party stepped through and made their way to the main hall of the dwarvish mine/city. Rather than seeing darkness and death and dust and spiderwebs covering skeletal corpses, they found themselves in the middle of a rather busy lobby of some sort. Goblins manned several desks, busying themselves with ledgers and weighing jewels and the like. Even more Goblins, some Orcs, and a couple of humans stood in line in front of these desks.

"Uh, what's going on?" Gimli asked somewhat stupidly, stunned and confused by what the Goblins had done to his ancient ancestral home, since such creatures usually just sorta pissed, crapped, and slept in the places they took over and never really bothered to modify them as such.

One of the Goblins who was manning a desk looked up from his ledger impatiently and pointed to a wall that had a rack full of paper objects leaning against it and said "Use the front entrance next time.".

Going over to the folded papers that had the word "Gringotts" in large letters and a coat of arms stamped on them in hopes of an explanation, each member of the party grabbed a brochure in their native language. It was from these brochures that the party was introduced to the concept of a bank, and exactly why they might need one in such times when Sauron's dark forces could raid their homes and carry off their money and other valuables, leaving them completely destitute.

"Whoa!" Boromir said as he read the last page of the brochure. "The Executive vaults are guarded by a Balrog!"