Thanks for all the responses!
I just want to comment that I do not have problems with money yet... although I am taking some financial risks that could change that.
Okay, so let's say we are in a world where you either have a house or you don't... either have a car or you don't... What are we looking at? More rental property and leases on vehicles? Is that so bad?
Now usually people live in smaller dwellings when renting because they know they are not getting any return on the money they put into the rent. Maybe there would be less suburban sprawl. Suburban sprawl seems to be a fairly wasteful use of land and resources to me.
Stopping usury would probably have the most impact on consumer debt, so maybe a decline in the economy as far as producing consumer goods. Less sweatshops in third world countries pumping out crap that most people can't afford but buy on credit anyways.
Investing in assets would be still encouraged if profit-sharing is still allowed, so maybe more people would borrow money to produce goods of value and then use the profits on that to finance their consumption. That sounds pretty good.
What about student loans, since these are mostly financed through usury? Maybe more people would start their education at community colleges and pay their way through school, or more grant programs would be developed by industries that need highly-trained specialists. I'm not sure, but I know that many students come out of college with some BS degree with little earning potential and crippling debt. Many more never graduate, but still have the debt to repay.
Maybe banks would cease to exist. Not sure. Also not sure this would be a bad thing. When the ponzi scheme we call the banking system finally collapses people will see banks differently. If the banking system collapses, there is no way the FDIC can cover the losses, there is just not enough money. They could print more, but not without seriously devaluing the currency.