Reddit user howtokrew recently shared this neat little photo of a carpenter bee that is living in one of his fence posts.

Carpenter bees (genus Xylocopa, subfamily Xylocopinae) are large bees that are often mistaken for bumble bees and are valuable pollinators. They are traditionally considered solitary bees though some species have simple social nests in which mothers and daughters may cohabit. [source]

Carpenter bees do not eat wood. They make nests by tunneling into wood, vibrating their bodies as they rasp their mandibles against it. Tunnels are near the surface so structural damage is generally minor or non-existent. [source]