A Couple of Minor Points
It's not about Wall Street or Main Street; it's about Elm Street.
Pundits and politicians alike have framed the financial crisis in terms of Wall Street vs. Main Street. Of course, no one lives on Wall Street, and few live on Main Street. Nearly every town has an Elm Street, though, and people actually live there. That's where they open their mail, and have to pay their bills. That's where they go at the end of their work days—or when they get laid off from their jobs. That's where they cry when a family member dies—perhaps because she couldn't get health care.
Trillions, Billions & Millions
Few of us have any idea how much a trillion is—or a billion—or even a million—because nothing in our experience is measured in numbers that large.
It's difficult to visualize meaningful examples, but I've made an attempt here. Did you know that a stack of a trillion one-dollar bills would be nearly 68,000 miles high—that a trillion inches equals about 16 million miles?