I have started crocheting a room size rag rug. I've got 2 colors done so far. I started with chain stitching 40, single crocheting the sides, and adding some extra single crochets around the corners. I go through a ball of "fabric yarn" pretty quickly. I have a whole bunch more ready to crochet in - over 15 more colors to go! See my previous post, Getting Started, to see a link for how to make your own fabric yarn. Check back in a few weeks for another progress update!
I haven't measured it with a yardstick yet, but I would estimate it to be 2.5 feet long so far.