Have you tried googling "stock scanner"
I use trade ideas. You can set the difference between open or yesterdays close & current price or the linear regression (angle) of a moving averages etc. There are other volatility indicators that they can scan for in real time.
They also have filters so that you can set a minimum daily volume etc to restrict what stocks are displayed in the results.
They also have a months free trial. There are other scanners that do this too. Like i said - Google.