there are a lot of fun projects in nick and tesla’s high-voltage danger lab. odin’s working on the “van tracker”. you soak the inner core of a highlighter in some water, then if you’re following the instructions you put the bag on the bumper of a van and poke a pin in it and use a blacklight to see where the van went.
not really thinking it through before i said it, i offered that it might be more fun to put the flourescent fluid in a squirt gun and write secret messages in the snow that you can only see with a blacklight.
highlighter fluid in a squirt gun – what could possibly go wrong!