Just a word of warning to those braving the crowds for Live 8 in Philly (certainly not me...although put me on a plane for London and you can bet I would be there rockin' out in a crowd of any size to see that line up):
It is expected that there will be over 1 million people in attendance at Live 8 in Philly and only about 400 - 450 porta-potties within the vicinity (
see for yourself).
1,000,000 people / 400 johns = 2,500 people per one lovely smelling temporary human waste container 
.
So it is my advice that, despite the heat and humidity, don't go overboard on the water and soda amidst the chaos of the concert....or else the scattered shrubbery of Philly might seem much more welcoming than a bathroom line of over 200 people.