I am looking for examples of Deligne-Mumford stacks whose coarse moduli space is $\mathbb{A}^n$ or at least an open subscheme of $\mathbb{A}^n$ whose complement has codimension $2$. (Thus the whole interesting part of the stack lies in its stackiness.) The stacks should "come up in nature". Obvious examples are classifying stacks of etale group schemes and, more interestingly, the moduli stack of elliptic curves. Are there more examples?