Here is a cool t-shirt folding contraption that is easily made from a couple sheets of FoamCore and a roll of duct tape.

[youtube gqq8eAl5Xyk&rel=1 nolink]

You will need the following materials and tools to make your own machine:
2-20″x30″ Sheets of FoamCore (available at your local arts and crafts store.)
Roll of Duct Tape
Razor Knife (Box Cutter)
Ruler
Pen or Marker

Plans:

Foam board cutting layout