The Pi-Star MMDVM Hotspot consists of an MMDVM_HS_DUAL_HAT module mounted on a Raspberry Pi Zero W. Currently, it is only configured for D-STAR, but is capable of a number of other modes as well.
On D-STAR, it is normally linked to REF002C in Nebraska, though it is occasionally used elsewhere. The hotspot is handy for when the local repeater/gateway (KD0PBW) is offline, or for using D-STAR while traveling. It is also a quick place to view recently heard stations on the reflector.