Real Time WordPress Emulator?

Does anyone know of a software that acts as an emulator?

Meaning,

It would run two windows,

Window 1 – emulated the wordpress install, including theme, etc…, and allowed you to make changes to the code, settings, etc..

Window 2 – emulated a browser and showed in real time how changes would affect the look in a browser.

This would prevent the annoying process of making small adjustments, and having to wait for the “Update” and the associated delay, then refresh to see how the changes look in the browser.

Links?

Thanks,