Years ago, I developed the interactive maps showing little flying planes on FlightAware. I left to focus on improving a site I started 20 years ago, Ptable, now the world's most popular periodic table website and available in 50 languages. Help keep Ptable an anomaly. How often do you find a vestige of the old Internet—an independent site beholden to no investors, no educational conglomerate trying to suck you into some co-branded walled garden? Your donation is a message that says you value the existence of sites like Ptable and want them to stay independent.