Annotate.tv - Optimize your learning on YouTube
Call of Duty - Call of Duty is a first-person and third-person shooter series by Infinity Ward.
Slid - Capture knowledge from online videos, courses, and webinars
Quake - Quake is a series of first-person shooter video games released by id Software.
SkillTube - A curated list of best courses from YouTube & other platform
Xonotic - Xonotic is a free (GPL), fast-paced first-person shooter that works on Windows, OS X and Linux.