I have made a few small indoor water fountains in the past, but I found them to be a bit irritating rather than soothing. They splashed too much and the sound of it water made me think I had left the water on outside. So, I decided that this is an item better left outside.
I just came across this nice DIY Bubbling Water Urn over at Gardener's World. It looks really easy and fairly inexpensive to make.