Generate the sounds of a babbling brook or a water-fall with SoX?

I got so inspired by this question "Generate White Noice to Calm a Baby", so I was wondering what else i possible to do with SoX...

• Is it possible to generate the sound of a babbling brook?
• Is it possible to generate the sound of a (large) water-fall?
• Is it possible to generate a wooden hollow sound - like of a wooden branch stinking a hollow trunk?

Know someone who can answer? Share a link to this question via email, Twitter, or Facebook.