You can also do this with an old OpenWrt router, which also gets you a management interface and a gigabit Ethernet switch as part of the plastic box.

I used to have such a bridge (OpenWrt on Netgear WNDR3800 hardware) Velcro'd to the underside of a TV cart, so that an appliance on the cart that only had Ethernet and 2.4 GHz WiFi built-in could do a more reliable 5 GHz across the room.