The WiFi Floatie is the maritime version of Andreas Reischles "Captive Intraweb" ESP8266 WiFi Throwie. Two LiIon batteries in the base of a marker buoy provide an ESP8266 WiFi module in the head with energy. An LED on the GPIO2 emits regular pulses of light and thus gets the impression of a distress-marker buoy.
The software is based on NodeMCU and Captive Intraweb and creates a wireless network with DHCP-, DNS- and HTTP-server. All requests are redirected to a web page where the visitor gets more information about this project.
The WiFi Floatie swims regularly on the Alster in Hamburg. About reports of sightings of the SSID "k1404.de/BF1" I am pleased.