Porydex is a combined Pokédex and Pokémon Showdown usage stats viewer, designed to make it easy to browse and analyze metagame trends over time.
Nearly all of its dex data is ripped straight from the games and is fully indexed and integrated into a relational database alongside the Showdown usage stats. This isn't always easy, but it makes possible some neat data analysis things.
All the code for Porydex is available on GitHub. If you're in the tiny midsection of the [software developer/Pokémon player/stats nerd] Venn diagram, feel free to check it out or make your own clone.
For more on Porydex and my other projects, check out my personal site.