Meteor is deeply integrated with the popular Font Awesome icon set. This means you can insert icons almost everywhere. You have 361 icons to choose from. Meteor has a build system which will include new icons as they are released, made available on theme updates.
Choosing so many icons and memorizing their names is a very hard thing to do. This is why you have at your disposal an Icon Chooser tool, which helps you insert your icons, and even search for the icons you’re looking for. How cool is that ?