OT -- ET, I referred to the fact that you can trade in and out of RYDEX, PROFUNDS, and POTOMAC Funds at Scottrade without short-term holding fees.
I currently use Fidelity for equities and TDWaterhouse for bonds. (I know, Waterhouse sucks, but they have the lowest fees on bonds that I could find.)
I'm in the process of opening an account @ Scottrade so I can trade the inverse funds cheaply.