This is a great book. Linnea's Windowsill Garden is a fictional first-person journal of a little girl who lives in a big city and does some very creative gardening inside her apartment. I found it at a secondhand store and thought of it being a tool to help my kids get into gardening.. but then I read it cover to cover and its currently sitting on my bedside table! Its really cute.
I assembled my gutter. Ours are aluminum, and I had some hesitation because they are rather large, but hopefully it will look ok. They look a bit like a piece of coving, so I figured I don't need to add any decorative wood box around them. Just the ends look a bit goofy because of the endcaps on the outside. I can always put a plant that will drape over that to cover them.
I used some silicone caulk. I didn't think to look at the store for some sort of food-grade sealer. I may line them in alum. foil or something. As for drainage I think I will just borrow some rocks from our landscaping and line the bottom inch with and and add some vertical straws though to help the bottom "breathe." I can't wait for the caulking to dry so I can plant it!
All and all, I paid a whopping $2.50 for the endcaps, so if this is a beta-version, thats ok by me!