A Stranger Things light wall built around a simple ESP8266 (ESP_01) module and a WS2811 light string.
The entire thing can be built for less than $20.
The ESP8266 runs a simple socket server looking for a string on port 80. Once one is sent, the line is parsed into characters and displayed on the NeoPixel board one by one. A simple one line command in Linux can send the string to be displayed:
#> echo "Im trapped in the upside down" | nc 192.168.1.229 80
Lights: https://www.amazon.com/gp/product/B017HAWXF0/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1
You'll also need a 3.3v regulator and a 5v power supply. The ESP-01 drives my lights fine at 3.3v but your mileage may vary. A level shifter may be needed if you have problems.