Birds are already unattainable as they are but the quickest and pretty interesting little bird to watch would be the jittery hummingbird.
Limited to watch from a distance there are tons of feeders available. But these humming-bird feeder masks put you right in the middle of all the action. The mask from eYe2eYe allows the humming-bird to feed right between your eyes for perfect observing experience. You might have to be patient though.
You get to look like Iron Man too, so win win.