At some point in US History there were some very Large Denominations of Currency, we all knew this. However, I don't think I was really all that familiar with the designs involved in a $1000, $5000 or $100,000 bill. The front sides look pretty standard - large head of influential political peson + ornate denomination - but the backs are the most interesting part to me. There's an odd (relative) sparsity to some of them that really sparks my attention.

via Mager