I’m surprised this was posted a year ago and I just came across it.
I feel it necessary to include the production cost:
In 2009 I decided to build a simple costume after the Mech in District 9, after about 30 hours and $76.00 I came out with this
Made with:
– Cardboard = $0.00
– Glue Gun = $10.00
– Spray paint = $20.00
– 2×4 Wood beam = $0.00
– Bungie cords = $5.00
– Fish line + $6.00
– Luggauge straps = $6.00
– Thriftstore paints = $4.00
– metal coat hangers = $0.00
– Rubber feet tread = $10
– door Screen = $0.00
– Metal shelf supports = $10.00
– bolts, screws & washers = $8.00
– backpack = $0.00
– 1 red LED = $0.00
dogmic 
Awesome!