Yes, someone is offering this incredible Ghostbusters Proton Pack replica on eBay. Auction page. Video of a similar replica, after the break. Click here for more pictures.

..pack is constructed of wood, plastic, wire, and plumbing fixtures and painted a flat black. It is held together using the great glue Goop! and lots of hidden screws to keep it in place. The lower center cyclotron with the 4 red circles is hollow to put lights in as well as the blue windowed box up in the upper left corner. The gun also has a hollowed out section which has electronics installed in it. A red LED bar is included and was working but must have been unhooked at one point