The mattress?
I'm half serious. I don't do financial gambling anyway, but one of the "rules" of financial gambling is stay liquid (cash) when "markets" are collapsing. However I don't think we're in kansas anymore. I do not think that central banks will be able to keep the stock market gamblers going unless they start buying shares outright in
massive quantities. Which, ironically, will be in practice bringing in soviet-style communism (the state owns the large enterprises) though desperate expedients to "save" capitalism. The political danger for the ruling classes is very high, they'll probably avoid this move. The japanese are doing it, but they were never ideologically wedded to "free-enterprise capitalism".
These markets are full of zombie companies, companies that never turned a profit, and whose stock and bonds are held speculatively by numerous investment funds, which themselves issued stock and bonds... it's a house of cards for the exclusive benefit of the managers of it all, a comparatively few sitting on top of the hierarchies of management.
It only endures because there's millions of "investors" who
think they benefit from it, only because they are so used to it, so caught up on its rules, that they can't imagine a different system which could benefit them more. But what happens to the beliefs of these "investors" when the rulebook is torn apart? That is what we're abort to see. Can the few people who really benefit from this system put in another that will both preserve them on top (as managers skimming a a big share of the wealth) and be accepted? Their only viable move currently seems to be buying through central banks, while obfuscating the implications of that (their social uselessness and parasitism as a group). Very dangerous.... for them.
We live in interesting - and I dare say hopeful - times.
Sorry I know that this isn't really what you were asking. But anyone giving you financial advice now should be honest and admit that times are extremely uncertain.