On some of the second floor windows at the office we have bird feeders, which have proven quite popular. All shapes and sizes of birds have been visiting and there's even a small bird bath. Some of the seeds end up being knocked over the edge, of course, which means there's a contingent of birds and squirrels on the ground happily munching along.
Why wait for seeds to come to you when you can go straight to the source? That seems to be the thought of every squirrel who's ever met a bird feeder and there's a whole market of anti-squirrel devices that attest to their tenacity. But, a second floor window is a pretty good deterrent. Sniffy here has been spending some of her/his spare time exploring each of the branches on the tree next to the window. None get close enough, even for a daring squirrel jump.