I found this on swiss miss's flickr site. Here is what she wrote: On my way to my office this morning, I came across a H-U-G-E wall of post-its saying 'TO DO'. I stopped and started watching peoples reactions. I can not even tell you how many smiles this art installation (?) created. People stopped, pulled out a pen and started scribbling on the post-its. This type of unexpected sighting is one of the reasons why I am so in love with New York. I could not have had a better start in the day. A big thank you to the creators.
UPDATE: This project was created by Illegalart.org in July 2007. Sorry, I'm a little late, but I still love it.