I have seen, and tied plenty of extended foam bodies. Mostly by tying the extended portion on a needle, and then tying that onto the hook.
I have also tied up quite a few different furled bodies for worms, and leaches. I thought why not try furling foam strips for an extended body?
A 6" foam sheet cut to about an eighth inch, width and tied to a hook. I then tied in a very thin piece of black darning yarn. As I twisted the two together, the foam wrapped around the yarn in a tight spiral. Once I had the body tightly wound, I carefully folded it to length, and tied in the other end. Be careful when folding the twisted yarn and foam, or it will twist back on itself it can become a tiwisted mess. It helps to fold the body over a dubbing needle and guide the body into a nice straight furled spiral.
I tie in a separate piece of yarn for the thorax, and wind a black hackle up the hook for before pulling the thorax over the top. Finally, I trim off the hackle on the bottom.
This one is tied on a size 12 scud hook.
Its a prototype, and I have not fished it yet.