These are kinda fun…I like the glowing ones best, but you have to leave it under light for awhile and then go in a dark room. The heat/color changing ones are pretty cool, but the twilight is the least dramatic.
Wowzers… This makes me wonder if I still have my ‘think geek’ smart mass from 15ish years ago.
I had this stuff for YEARS. I think I finally threw it out: