LED Magnetic Digital Graffiti.
This set of 20 different LEDs each has a battery and a magnet attached. Pull the tab to activate, then toss them on any ferrous metal surface… they stick and glow brightly announcing to everyone in the vicinity that you were indeed there. But make sure you stick the LED Magnetic Digital Graffiti on stuff you own, or are able to remove them later… because gone are the days when you can post funny battery powered LED signs all over Boston and get away with it.
