It's true, but only for Wintergreen. It's called "triboluminescence". I've done it with wintergreen Lifesavers, but not Altoids. It's a very low-intensity, bluish "spark".

Maybe the Fresnel lens from your PSK might help magnify (or would that be focus?) the spark, plus you'd literally have to hold your mouth right! <img src="images/graemlins/wink.gif" alt="" />

David