In 2008, I was concerned about the "full faith and credit" of the US government, not to mention all the banks. That risk was very high then, and is down considerably now. But if you are still worried about that, then get out of stocks, bonds, banks and US dollars. And if all those crash, real estate will too. Doesn't leave much. Gold was a good bet in 2008, but still hard to predict. It didn't go up when it should have, it was significantly delayed. I am no expert in gold, but I watched the fundamentals for a short while, and gold doesn't seem to perform like it should. On the other hand, I saw that in the UK water market, the stock price was woefully behind well-known fundamentals. I just wouldn't expect that in gold. But I'm not a stock analyst so I shouldn't be extrapolating.
For my money, at the very least we should diversify assets, pay down as much debt as possible, and watch our banks' stability. If it's offering low interest rates, that's a good thing. High rates that just went down, watch out! Check this site periodically to make sure your bank is not on the Unofficial Problem Bank List (sortable by clicking on headings): http://calculatedriskimages.blogspot.com/2010/10/unofficial-problem-bank-list-october-1.html
I told my Aunts that their bank was on this list, and they didn't listen. Then it failed.
If you have a lot of money in banks, use the FDIC's EDIE to make sure you are fully insured. Your insurance rises by using multiple accounts with different vestings (ownership types, eg. Individual, Joint, In Trust For/Pay on Death, etc).https://www.fdic.gov/edie/index.html