I personally love the idea that we all perform a song when we see a person litter. It will be entertaining and funny, as long as we don't make it too confrontational. The only issue is if we can and are willing to sing in public.
Here are some links to some of the videos we brought up. Maybe by watching these we can come up with our own original idea. One that we don't have to sing in preferably.

http://www.youtube.com/watch?v=3ZcNXe20dXI

http://www.hulu.com/watch/225223/what-would-you-do-disabled-womans-dog-dilemma#s-p2-so-i1

http://www.youtube.com/watch?v=HRfjLfyXYlA&feature=related

and i thought these were just kinda funny

http://www.youtube.com/watch?v=HRfjLfyXYlA&feature=related

http://www.youtube.com/watch?v=_PR5mXyYils&feature=BF&list=PL01C48FEF416CB290&index=34