Comoving stars include a range of objects from wide binaries and multiples to moving groups and open clusters. I will discuss why they are interesting for studying the Milky Way, stars and planets and describe our recent work to find candidate comoving pairs using Gaia DR1. In order to select pairs of stars more likely to share the same space velocity, we build a probabilistic model and marginalize over the unknown parameters. We use the fully marginalized likelihood ratio to select comoving pairs. Some of these pairs form larger groups by sharing mutual comoving neighbors, many of which correspond to known open clusters in the Milky Way. Additionally, I will describe an example of differential abundance analysis of a comoving pair that led us to conclude that rocky planetary accretion has happened in a nearby Sun-like star. I will conclude with future directions and outlook.