Save the little soy sauce fish from take away sushi! They make a lovely window garland or would look great hung individually on the tree. We filled them with water coloured with food colouring and painted the tops with different coloured nail polish.
And save the packet too. Why? Well, sushi containers are perfect for shrinky dinking. My daughter Mattie made this (Kesha themed) charm bracelet for her sister. The diamond charms are sushi packets (the rest is shrinky dink frosted plastic that you can buy from a craft store.) Mattie drew on the plastic with a sharpie pen and used a hole punch to make the hole. Then into a very slow oven and watch it shrink and thicken. You can place something flat on top when it comes out of the oven to ensure it doesn't curl.
And while we were shrinky dinking, we made these snowflake bauble necklaces for the twins. Blue pencil on frosted shrinky dink.