AnnMarie Thomas (whose work has appeared in MAKE Magazine as well as Make: Online in the past, links below) created this adorable LED costume for her daughter. If you can’t figure out how to make it by looking at the pic, she created an Instructable to guide you. (I love the anode/cathode leggings!)
From the pages of MAKE:
MAKE Volume 22, Remote Control Everything
Automate your world with remote control. From pet care to power outlets, from toys to telepresence, we’ll show you how to add a joystick, push-button, twist-knob, or timer to just about anything. Don’t forget, subscribers can always read the digital edition here.