The materials will end up running you somewhere between 0 and 20 dollars.
1. Disposable camera w/ flash
2. Soldering iron and solder
3. A few square inches of 1/4" thick wood, acrylic, glass, etc.
4. Super glue / hot glue
5. Momentary push button switch
6. Syringe tips (Come with ink cartridge refill kits)
8. AA battery holder