On this short video Daniel Norton from Adorama demonstrates how to use a reflector as a main light.
We typically don’t consider a reflector as something powerful enough to be used as a main light but in certain situations and given specific looks this can be done as demonstrated by Norton in this video.
So for this video Norton does use a light (strobe in this case) which he raises upwards above the head of the model and use it to light the reflector which bounces the light into her face. Norton shots a side portrait of her and shows how it differs from a previous one he took where the light was coming from the the light itself.
If you don’t have a reflector (which is usually not very expensive – depending on the size/brand) you can make your own DIY reflector – you can find some videos on LensVid here (as well as this simple one).