Latex Perfection: Unfortunately, no longer nearly so useful as it once was, due to the difficulty of compensating for all the exotic sensoria of all the species out there, never mind the sheer range of possible sensors. (Mass-market cameras, for example, tend to cover everything from high radio bands through X-ray, in EM spectrum terms.) Disguising yourself as someone else tends to involve growing clone-bodies, or bodysculpt, at the very least.
Bioluminescence Is Cool: And available in several varieties from your local bodysculpt clinic, along with some interesting variations on the theme of chromatophores. Ah, fashion industry, what will you bring us next?
Also used for some more practical purposes, like non-electrically dependent emergency lighting, engineered glowing trees for streetlights, detectors of this and that, etc., etc.