I googled "Collaboration Poetry" and stumbled upon a collaborative poetry page on About.com. Here, I found The Albany Poetry Worshsop. The Albany Poetry Project is a collection of poems written online via messageboard style. Each poem starts with a line from a well-known poem by a familiar author. Readers/writers then create a brand new poem by posting lines of their own. Each contributor is only allowed to post one line per visit to the website.
The poem I found most interesting is entitled, "An August Afternoon." It was completed October 27, 1997. The first line is from a poem by Bronislaw Maj.
Please visit following link. It will lead you to a page of poems by The Albany Poetry Project. Click on "An August Afternoon" to view the poem in original format. Also, feel free to check out the other poems.