Yertle The Turtle
I bought a used El Toro dinghy sail off eBay from $26.  I laminated my own 14' mast out of 1"x3" pine boards and made a boom out of a rounded off 2"x2"... 

The sail is laced to the mast with small line and I made my own gooseneck out of a piece of PVC pipe.  The whole rig probably cost about $40. 

Buddy's daughter, Maggie helped rig...
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