Screener with custom criteria

Hi, Does anyone know of a free public screener that allows you to screen with criteria that you can build? For example, most screens have something for ROE (just net income / equity). But what if I wanted to substitute CFO for net income, and screen for CFO/Equity. Are there any tools online that will allow me to do that? thanks!

I have searched high and low for days and nights to find the best screening device. It is AAII’s stock investor pro. It is better than expensive tools for some things. It costs $200/year but you can try it for free (cancel anytime in the year and get all your money back). is a good one.