As is typical with my builds, I shunned spending money on anything but tools. This was made from scratch with nothing but love (or insanity) and elbow grease. I really don't think buying plumbing parts or hacking a tap/puck light is nearly as cool as crafting every last piece. Total cost of materials for this should be under $10 if you creatively recycle and plan ahead.
I started this project over 2 years ago but forgot about it through my senior year and first year of grad school. I got really bored recently, and with my own apartment (and work space) decided to stop being a slacker and start putting my tools where my mouth was.
If you want me to do a show-and-tell video, as well as explain some of the finer details of my arc reactor, let me know in the comments below. I should have a blog post about this project in a couple of days... /weeks... however, so check up on winstonmoy.com at some point for the goods.
Music used: The Land of the Wizard by Machinimasound.com
UPDATE: I have a video of me wearing this to illustrate how it looks --> http://www.youtube.com/watch?v=U9atTRTdl3E
Double Update: Instructional Video Companion Post that includes more information than I could fit into the annotations here: http://www.winstonmoy.com/2013/03/arc-reactor-construction-montage-instructional-companion-post/