***UPDATE 5/4/10: If you make your own ghostbusters proton pack, post some pictures in the comments below, and I'll send you a patch!***
***UPDATE 9/22/11: Check out the October 2011 issue of Popular Science (which is out right now) to see a brief blurb about me and my proton pack!***
Step 1: Make a Ghostbusters costume
There are many resources for building a proton pack out there. I've got my slideshow from last year, as well as a more detailed instructable on how to make a kid sized Proton Pack, which could easily be scaled up to full size. I also recommend this instructable, as well as gbfans.com
I picked up the flight suit from ebay member direct-pb. This company really came through for me. The suit was good quality and very inexpensive.