There are ~56 trillion USD in the M2 set combined with everything else. M2 is all of the money loaned to banks in the form of deposits (which is why you get an interest rate, and also why they can invest it in any way they see fit) plus all of the money in money market accounts. Everything else is M3 money, that the Fed has given up counting.
This information is readily available from their website, and convenient links to it can be found at Wikipedia.org.
For the record, money is conjured into existence via the borrower’s promissory note. Based on his word, track record, and the collateral the borrower may or may not yet own, the bank approves the client for credit. Their promissory note is swapped for a bank promissory note. Banks have charters to convert promissory notes into fiat currency, and they do quite frequently. Before the bank lends the money to the client, it technically owes them money. The next step simply involves typing in the appropriate dollar amount into a computer and transferring the money the bank now owes to the client to their account may provide them with a checkbook.
Upon receiving these powers, the bankers diluted the money supply so that they would have absolute control over it. They also established the Federal Reserve to limit the powers of Congress over the country’s economic affairs.
Most of our currency is debt-based, and actually needs to be payed back. If everyone stopped paying their bills, nearly everyone would be bankrupted, and those who weren’t would have their bank credit accounts wiped out. Only those who own real property and store their cash outside of the banking system would be safe in the subsequent deflationary spiral.
The system is doomed to bankruptcy as it is dependent on exponential growth of the real world economy, which is an impossibility. The reason for such dependence being: the interest on the loans cannot be paid back because it actually doesn’t exist in the overall money supply because almost all of the money in existence was made in the same manner; without continually manufacturing cash and inflating the money supply, enough money will not be in existence for most to pay off debts, and an immense foreclosure process will begin; new debt money can only reasonably be conjured up if there are ample resources in existence to put up for collateral, and merely to prevent the buying power of the currency from becoming greatly reduced in the process of mass conjuring/inflation.
The US dollar, the Euro, the Yen, and most other currencies will undoubtedly collapse. This system works for places with the potential and desire for exponential growth. China has only been using this system since the late 1980s, and so will take somewhat longer to collapse. It is currently in a major bubble; one that will burst sometime soon, though not necessarily large enough to completely ruin them. Cuba, Iraq, Afghanistan, Libya, and one other had absolutely nothing to do with this system; I wonder why the middle two mineral rich countries were invaded? Countries like Canada, Australia, India, and much of the ASEAN states are set for stability, in comparison to the rest of the world. Eventually, however, it will all catch up to those not in the elite banking class, and ruin them—to the benefit of all of those who are in that class.
The solution is simple: governments should outlaw the practice once it is realized that their economies are in, or will be in, critical condition and be prepared to print debt-free fiat currency withing reason. Exponential growth is not possible on a finite planet. The commercial banking system could be implemented wherever necessary, but should be prevented from existing in countries that are no longer in need—or want—of it.