The world's most brazenly hidden bird -- the common potoo 

The incredible common potoo isn't much to look at -- so much so that you'll struggle to see it at all! In a bold display of camouflage and mimicry, this bird pretends to be a broken tree branch. To do so, it poses absolutely still, bravely evading predators in plain view of them. The potoo in this video is particularly fearless -- switch the quality up to HD and watch to find out why she's so determined not to be scared away from her perch.
Although you might not see them, the common potoo is, indeed, common in at least parts of its range. This rage extends from Nicaragua in Central America, south to Argentina. Six other species of potoo are known of, all generally similar in appearance and all performing the same posturing cryptic behaviour. Potoos have large eyes and a huge mouth -- features they share with the closely related nightjars.
As mentioned in the video, potoos squint their eyes in order to not expose their bright yellow irises and give the game away while keeping track of potential predators. Fortunately for them, potoos have an amazing, subtle adaptation -- slight notches in the eyelids, which are presumed to enable them to see even when their eyes are apparently closed.
Again like the nightjars, the eyes of the potoo are highly reflective to artificial light. Being incredibly cryptic, their eye-shine means that a night time stalk with a torch light is the best way to locate them.
If you've watched the video by now, then you'll know that this potoo has a young chick. Potoos lay just a single egg, and most commonly do so in the slight bowl of a tree branch or broken stump like the one in the video. Potoos form monogamous pairs, sharing responsibility for raising the young. Some evidence suggests that, during the day, egg incubation and chick protection duties are performed by the males of breeding pairs, with the females taking the night shift.
However, over a 36-hour period, there were no 'shift-changes' in this potoo family, making for one no-doubt exhausted parent who we have arbitrarily (males and females have similar colouring) designated as the female!