felt/embroidery style crafts are super cute to do and pretty easy. making small photo frames out of felt, making a garland, making cute felt crowns or hair accessories. i am also partial to customizing clothing with my friends, making weird little matching shirts or using a potato/eraser to make a little stamp and stamping little stars or hearts onto my jeans.
you could also paint or draw each other, make bracelets out of beads and string, or do some crazy artsy makeup. the best thing to do with your friends is to pretend you are all kids again and do things that you would have done on a play date.