In the fall of 2015 I created a birdfeeder using a single sheet of 24″ x 12″ birch plywood. I designed the three dimensional object in two dimensions using Illustrator, then laser cut the finished product at my local makerspace. The design was revised several times, although every single bird feeder that I cut has been completely functional. The first one was created to hang (which it did) but then I discovered suction cups on Amazon for about a quarter each so several variations of window feeders were born. The birds clearly like them, as you can see in the video.
I also created the music for that video. A lot of people have asked me if they can buy a feeder. As of now, the answer is no. If that changes I will let everyone know via my email newsletter, which you can sign up for below. The wood is left untreated. And to my knowledge, no birds have flown into the window(s) or been injured by the feeder.