Streams or Screams?

It's me again.

Having too much time on ones hands to work out in the 'yard' makes the
imagination run amok with ideas for making the whole place look like a
wooded wonderland.

Having the pocketbook of a retiree, makes one's imagination often come to a
screaming, frustrated halt in nothing short.

I have been looking at my place and thinking that I would like a little
stream. There is no natural running water but if it were to run from up by
the house to the pond (call it 200 yards as a rough guess) it has an already
natural pathway from where the rain runoff travels.

If you do a stream, do you have to do filters and all of that?
Are the pumps expensive to purchase and operate?
What are the real ups and downs of manmade streams?
Do you think it feasible with the distance I am dreaming of?
Are they terribly involved to build or can you just dig a ditch, put some
rocks in to prevent erosion and turn it on?

Thanks folks for hearing my stupid questions and not throwing me in the
pond.

Kate