My sister and my mum in law did this as a suprise for us, only they projected them onto the wall.
They found photos of us from everywhere!
It was a nice touch.
Word of advice though if anyone is thinking of doing the same. We was in an old barn and not a single wall was straight and there was lots of beams everywhere as well as sunlight streaming through the windows. So the projections for that reason were actually a little tricky to see, but I loved it none the less.