Here's my entry. This STUPID easy!
I just cut a crapload of 8 inch squares
out of a bunch of jeans
and made a blanket of sorts. Just sewed them together, nothin' fancy. Then I took a peice of plywood
the size I needed for the headboard and stapled
around it and then did the same with the jean blanket. Bolted it onto the frame of the bed and VIOLA! instant headboard.
If you'll notice in the pic, I ran out of squares so I had to sew together some scrap and then use my 8 inch template (made from the back of a notebook) and cut more squares. My son loves it!