I think it's been done before
I also think you're going to get really good at this lighting business Neil - it's great to see you experimenting! This is a technique used in the movies all the time - if your shooting schedule says "evening sun through the window", well you better have some sun on the call sheet! I find film-set lighting to be a great source of inspiration for some mood and drama in still photographs.
I do this *all the time* on location - just remember that the sun is small from our point of view here on Earth - so if you want to emulate direct sunlight, a smaller light source such as a speedlight is ideal. You can get away with a small reflector too, but my Sunlight of choice is the Godox AD200 with the rectangular Fresnel head on it. Also, add a half or full cut of warming gel for that evening/dawn look. For soft even daylight from an overcast day, cover the window with a diffuser (a white sheet will do) and get the light far enough away that it illuminates all of the diffuser.
Of course, the one aspect of sunlight you can't emulate is the distance, and a fake sun will make shadows obviously radiate away from a close light source rather than appear parallel to each other. Most viewers tend not to notice this though
If there are multiple windows, you can use multiple suns to get the shadows through windows parallel from room to room (although the shadows cast in each light will still diverge).
I don't have any SFW examples really, so rather than plaster the thread with nakedness, here are some links (which are Not Safe For Work)
Two light sun emulation
'', an image by Owen Lloyd.
purpleport.com
One light sun - grubby windows are a gift
'', an image by Owen Lloyd.
purpleport.com
Volumetric rays (demonstrates the divergence you wouldn't see from the real sun)
'', an image by Owen Lloyd.
purpleport.com
Real sunlight for comparison - parallel light shafts:
'', an image by Owen Lloyd.
purpleport.com