make a tissue box guitar.......you need....
an empty tissue box
any kind of string or yarn
a paper towel roll of wrapping paper roll
now just connect the paper towel roll to the tissue box on one end...put a hole there and maybe use some tape and/or glue.
then just add the string to the end of the paper towel tube and connect to the end of the tissue box.
connect however many strings you want and strum away =P