Borophene—two-dimensional (2-D) atom-thin-sheets of boron, a chemical element traditionally found in fiberglass insulation—is anything but boring. Though boron is a nonmetallic semiconductor in its bulk (3-D) form, it becomes a metallic conductor in 2-D. Borophene is extremely flexible, strong, and lightweight—even more so than its carbon-based analogue, graphene. These unique electronic and mechanical properties make borophene a promising material platform for next-generation electronic devices such as wearables, biomolecule sensors, light detectors, and quantum computers.