One of the coolest backpacks ever! The Ghostbusters Proton Pack Backpack looks just like the packs worn by Dr. Peter Venkman and Dr. Egon Spengler (not to mention Stantz and Zeddemore). The cool part about this backpack is that you can use it as both a Halloween costume and a regular backpack. I ain’t afraid of no ghosts. Who you gonna call?