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.
Here are some design notes when it comes to modern pergola designs. The most common pergola design is to have decorative and somewhat rounded ends on the beam. The easiest way of creating a more modern pergola is to do away with the decorative ends.