Goal Light is an open-source software/hardware version of 'that goal light project' by 'that beer company'.
Theirs costs $150 and requires a smartphone. Mine costs about $50 (for parts only)
The code pulls the data from the NHL website, scrapes and parses it, gets the current score of your favourite team, then lights the light if the score is a bigger number than the last time! (The delay you see in the vide is a result of NHL.com taking 30-45 seconds to update/verify the goal... I'm looking into options around mitigating this...)
This work is licensed under the Creative Commons Attribution-NonCommercial-Repurcusssions 3.0 Unported License. The code is written in Processing, utilizes the Arduino, and is available on my GitHub.
Thanks to Leó Stefánsson and Lee's Electronics.