I was reading ETS's list for an altoids tin personal kit and saw that tape was used to make the lid into a signal mirror. This prompted me to do a web search for "mirror tape" and I got hits. Here's the first: http://www.identi-tape.com/deco-mirror.html

Has anyone tested any for use as a signal mirror? From the picture it looks a lot like duct sealing tape, only shinier.