These are so easy, yet I would have never thought of it. Collect foil tubing, either from repairs around the house or buy it from your local store. Different sized tubes gather different sized pumpkins. A length of pipe can be used for the stem and dried brush or craft grass in a brown or green can be used to accent the pumpkin.
The best part of this project is how simple it is to make right. All you need is a few minute, some spray paint and tubing. For Halloween you could even cut out a Jack-o-Lantern and light it.