Maybe it's just me growing up in SoCal, but....
Anyone remember an elementary school game involving stringing rubber bands into long ropes and looping them around a pole? The idea was to jump over them at different heights: ankle, knee, waist, chest, *neck*, *top of the head* -- the trick was to catch some good air and really fold your knees cos once your toes are over, you're fine. Assuming you land ok.
It was called "Chinese jump rope" at my school. They used the poles that supported the covered walkways... (ah, California: each classroom in its own building.)
Anyway, they made these ropes by taking a bunch of bands and folding them over, then taking another bunch of bands to link to it. Just tie off the end when you're done. It's hard to describe. Look at the seams on a baseball/softball to get an idea of what one link looks like. Anyway, you could make some seriously thick ropes with rubber bands. Braid those ropes together and... I still wouldn't bungee jump with it.
But I am tempted to buy a few pounds of rubber bands, now.