Philadelphia airport is so hot that you need plenty of liquid. We found ourselves sitting next to an advertisement for 'LIFE WTR', masquerading as an art installation - one of many that brightens up this airport. You might be able to magnify the picture and read the text. The picture on the right is intended to represent birds in an aviary.
I found that gazing at these images for a while during our 8 hour (yes, really!) stopover was quite calming.