I am a regular Large Format user, shooting 5 x 7. One of the problems with this heavy gear and reliance on a tripod is that finding the just the right angle to shoot from can be very difficult. I found that my Minolta MG had a great focal length, I did some calculating and learned that a 240mm lens would on my 5 x 7 camera would have the same perspective. Now I pop the Minolta in my pocket, and use it to explore all angles while visualizing large format images. Works great, and I also have a mini version of the pictures I take.
Try it with your mini camera!
Dunno about the viewfinder aspect but I read that with the cheap digicams around now, some folk use them as a light meter. 'Bout the same size as the old Weston Master etc, and actually has other uses, too!