I hosted a panel at IBFC over the weekend discussing various techniques available for working with EVA craft foam to make props and armor. As part of it, I made a simple dagger pattern that can be made from layering pieces of fun foam/"foamies" together.

These are example daggers I made using a modified pattern (extra points on the cross guard). One is built from all grey foam where the other I used multiple colors of foams for the different parts. I even added a ribbon wrap on the grip for that one too.

Dagger pattern to make your own: http://www.furaffinity.net/view/24254548/
List of typical tools & materials you need for working with EVA foam (not all needed for this particular project): http://www.furaffinity.net/view/24254518/