Now that Bill Cosby got an early release from prison, my friend Paul brought my attention to the company Undercover Colors that developed a clear nail polish that allows you to check a drink for drugs by dipping a fingernail into the drink. The nail polish changes colors if drugs are encountered.
Brilliant! And love that it was founded by NC State students (didn't to school there, but did participate in their rugby club as a townie).
It looks like the product has evolved slightly to a more typical strip test kit though. I supposed the manufacturing costs proved too high? Hopefully they are still working on the more subtle version.