[Pharaoh]

Good point Sergei. Even if you get a broker that pays you a pile of interest on your unused margin (a few brokers do pay some interest on this), once an account gets past a certain size, there's no reason not to move some of your money off into a "Trading Reserve Account" at a good bank (NOT the same bank your brokerage uses). This is one more way to shield yourself against total loss in a bad situation.