A sport coat that has hundreds of little lights sewn into it.
I once saw a local musician play the guitar and sing in a small venue. For one song, they dimmed the lights on the stage almost completely, and the sport coat he was wearing suddenly "switched on" and he had hundreds of tiny little light beads sewn into the jacket that you could not see before. They were not string lights, like for a Christmas tree. They seemed to be much more LED like, and bright, and most of all, small to the point of being invisible.
I hate to be a copy cat... but I want to make a jacket like this too. I do not care if it is portable. i.e. if I have to plug it in, that's fine. Anyone have any ideas for where I might start?