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) 7. Wire 8. AA battery holder