Back in October 2007, Bill Bryson (not the author, a different Bill Bryson) printed out his boarding pass on a giant sheet of poster paper about 3' x 1.5'. He had quite an adventure.
After my extremely long flight down to Minneapolis I headed into the World Club (NWA's rendition of the Board Room). When you enter their facility with an Alaska Airlines board room pass you need to show them a NWA ticket to get in. So I handed them my board room card and unrolled my boarding pass on the counter. The two ladies looked at each other and started laughing. They called over the other people working in the world club over to take a look. They asked me if I had won a trip or something. I told them that I was just doing it to get a smile out of people. They laughed and told me to have a nice day. One of them said that they'd like to see the gate agent try to scan that thing in.
(via Uncertain Principles)