Cut you t shirt from one shoulder to the other. Cut from the sleeves to the bottom. Turn it upside down and stitch on three sides. Turn it over and fill it with cotton. After filling, stitch the fourth side or add a zipper.
Lay your shirt on a flat surface. Sew up the bottom. Increase the neck hole by cutting it wide through the help of a bowl. Cut away the hems. If you have a jersey shirt, it is better as it is sleeveless already. You have a grocery bag ready to go shopping.
T shirts make great laptop covers. Fold your t shirt upto the chest. Measure the size of cover you will need for your laptop. Sew it up and cut off the excess with the sleeves. If your t shirt has a pocket, leave it as it is on the front. It can serve as the brick holder.
Decide the size of napkins that you want.Cut a square fabric out of your t shirt one inch greater on all sides. For a napkin size of say 8 inches, cut a fabric of 9 inches. Fold the sides of the square and stitch them. It is that easy. The napkins are surely going to be talk of the table. Experiment with innovative designs and patterns.