Rain overflow feature?

When the water tanks are full, I want to have the overflow go into something decorative and fun or useful.  I'd like any ideas you may have on how to do it.

1. Watering some kind of otherwise hardy plants

2. Running a boar scarer or other noise maker like chimes

3. Feeding an indoor water fountain that only runs during overflow rains

4. Perhaps some crafting use?

5. Perhaps growing some short lived seasonal plants like nettle for fiber?

Any other ideas?

My suggestion would be to pile up some rocks and make a water fall similar to this thread:

https://permies.com/t/65359/sculpture/art/water-art-water-features-water

Or make a pond or build a hugelkultur bed as described in this thread:

https://permies.com/t/127073/store-water

I'm thinking of making a wicking bed in the site where I hope to build my polytunnel. My idea is that it will take the overflow from my rainwater barrels. Currently I have a hose connected to the top of one barrel, and it just overflows onto the grass a little way away from the house, that happens to be where I hope to put the polytunnel.