Waterfall stacking: Can you leave your tripod and ND filter at home?

I can understand the desire for creating the smooth "smoke in a wind tunnel" effect to portray tranquility, but the boiling sandstorm cloud effect has its uses too. I can think of some scenes where the juxtaposition of rough waters with a tranquil background would result in a pretty interesting photo.

I'm happy to have this tip in the back of my mind in case I ever find myself without an ND filter.

--
Photography - It's not what you look at that matters; it's what you see.
Galleries: http://www.photo.net/photos/teru
http://www.fotop.net/teruphoto