Sneak peek at LumenRT's upcoming real-time lighting engine. It simulates indirect lighting (GI) in real-time.
Of course, this is nowhere near as accurate as the full physical lighting calculation done in LumenRT, but has the advantage of reacting instantly to changes in your scene (e.g. changing time of day, adding new objects, editing materials...).
It will enhance Draft mode to give you an idea of the final look with LumenRT's better physical lighting.