Looking at doing this under our back deck, but will be interested in the comments here. Was looking at the corrugated tin hung on tapered runners into a gutter. Don't have any trees around the back, so debris shouldn't be an issue. I was thinking I'll probably have to add a spacers or use a non-wood material for the tapers so no moisture gets trapped there or at least doesn't dry-rot the material used for the runners.
“A determined soul will do more with a rusty monkey wrench than a loafer will accomplish with all the tools in a machine shop.” Robert Hughes (1938-2012), Australian art critic