Giant Working Apple iPhone 4
Featuring a 40" LED LCD panel hooked up to an actual iPhone 4, this massive costume weights 75 pounds, is powered by a 12 volt battery with 2 hours of battery life, and took 40 hours to make!
Real(ish) Working Iron Man
There's cosplay and then there's cosplay. Fitness instructor Anthony Le goes all out with so many moving parts and an excellent fit and finish. The mask even flips open and closed. If you're a fan of Iron Man and cute kids(!?) you'll need to check out this child's version too.
Apparently not, as the black turtleneck sweater and jeans is considered a tribute by many. Don't forget to grow a beard, grey hair, and throw on some glasses.
Giant Working Camera
Tyler Card goes big and fully functional with his working digital SLR camera costume. It features an LCD display, flash, and wireless remote control. He can even trigger his remote strobe lights.
Thomas Bangalter's Daft Punk Helmet
Extremely long and complex build, but absolutely worth the effort. Over 4 months, 350 LEDs and a custom iOS app are just a small bit of what it took for this build.
Gaping Hole In Torso
Mark Rober (a NASA spaceship engineer by day!) connects two iPads and uses FaceTime to simulate a gaping hole in his chest. Expensive and requires WiFi but sweet!
If you don't mind people bent down in front of you playing with your jostick, this playable Pac-Man is a well-done costume that just requires a bit of woodworking know-how, an iPad, USB gamepad, and a few other parts.
Who doesn't love themselves some Angry Birds? This costume is only 20 bucks and doesn't require any thought or effort. You might just find yourself getting tossed around the party, though.
Beating iPhone Heart & Other iWounds
This sophomore effort by Mark Rober brings chest holes and tech to those of us with just one smartphone. His iWound shirts and smartphone animations simulate all kinds of horror from within your chest / under your shirt.
(Images: as linked above; Steve Jobs photo by Flickr member Steve Ganz, licensed under Creative Commons)