We've updated our badges to include support for SVG format. This means they will display just beautifully on retina displays. Such pixels. The badge has also been tweaked a little so that people know to click on them to join the chat.
Here's a sample of what the new badges look like.
If you visit any public room on Gitter, just click the settings button and choose Share this chat room.
Bonus: we vectorised the badger and you are welcome to download it . Because everyone needs a vector badger handy for when you need it most.