This one is really interesting, cause when i applied for a mortgage loan for my house many many years ago, i did read up on how banks give loans, and it's downright criminal.

If I (a private person) give you (another private person) a loan for a house that costs 300.000 euro's, i first have to have 300.000 in my account, then i transfer the money to you and you can buy a house using this money. Each month you'll have to give me a fixed percent (for simplicity's sake, let's say it's 5%)...
If you're going to pay back the loan in 30 years, 'ill make 279,767.35 in intrest over those 30 years... Pretty neat huh.... I'll almost double the amount i loaned out to you.

When a  bank gives you  a loan of 300.000 euro's, they don't have to have 300.000 on their books... They can just create "virtual money" which they loan out to you. IIRC, the percentage is actually a little less than 10%. So, a bank can have 30.000 on it's books, and still give out a 300.000 loan AND get 279.000 in intrest. They don't double their money, they actually multiply their investment by a factor >9...

It's downright criminal, but it's legal... This is why we need to be our own bank... If you don't own 300.000, you shouldn't be allowed to loan out 300.000.