Log Bird Feeder - 23 DIY Birdfeeders That Will Fill Your Garden With Birds (my note: I haven't looked at all of these, but at least one is a terrible idea. The window birdfeeder -- birds could fly into the glass and hurt themselves.
corner gallery wall - without the specially made corner frames. Would need to be on a corner that is in an open area; this would be really overbearing in a tight hallway. But in the right space it could look amazing. Very art gallery.