I added LEDs and a Lily Pad Tiny Sparkle to each of these leg warmers, because my daughter wanted me to.
I've since learned that stretchy leg warmers and non-stretchy thread don't work well together. I broke a thread taking them off and found myself wishing that they sparkled faster.
I am abandoning this idea in search of a more practical one...such as creating a blinking hat like the one that I saw an Essex senior wearing at the mixer! She used LilyPad and Adafruit neopixels that were individually programmable! My supplies are in the mail!