A rope bracelet - reminds me of making friendship bracelets back in the day. My right second toe used to go numb because I'd hook the end of the bracelet over it, and then knot embroidery floss for HOURS.
This pattern is for knit slippers, but I can totally see using a wool sweater and cutting and serging slippers from it! Home Slippers - DIY. this is knitting, but I bet I could use this to crochet some