Wheat paste is extremely inexpensive and simple. As a glue for paper projects it can be just as strong as white Elmer's glue at a fraction of the cost. It only requires flour and water and can be made in about 10 mins. It uses a 4 to 1 water to flour ratio and you can make as little or as much as you require. You simply heat the mixture until it thickens then let it cool. I does not store well but can be kept refrigerated for a couple of days. I make it the same day I use it and throw away any leftover. The glue is not waterproof but does create a hard and strong bond. I use it for making fireworks and rocket motors. As a side note some people say the storablity can be improved my adding things like salt, sugar or peppermint oil. I have tried many without good results.
The materials I use:
All purpose Flour
Water
Cooking pot
Mixing spoon
Measuring cup
Heat source