Here are some pics of my project in progress, including a facsimile of the goal at the end. From the "upright" example picture, shown to me by Eyebeam's Ayah Bdeir, I will be adopting the umbrella motif, as well as (more importantly, I think) the rug which establishes a sense of place. Updated: take a look at the Instructables piece for the coupling. Feel free to leave a comment if you have any insight on how I ought to proceed.
Bicycle Trailer Hitch - Quick Release hose coupling. - More DIY How To Projects