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US: Hobbyist modifies clear computer case to use laser beam illumination
The laser in this photo is green, but other photos show it as red and blue (e.g., using a three-color or RGB laser module)
The cost of the laser mod was said to be about USD $50.
It appears the beam is fully enclosed within the case, so it could not enter a person's eye. However, if the case was jarred in such a way as to knock one or more mirrors out of alignment, then laser light could exit the case window.
Also, during construction or when the case was open, there would be a potential laser safety hazard.
One story on a gamer website noted the potential for eye injury, and to follow any applicable laws and regulations on laser possession and use.
From the Reddit r/nvidia subreddit, via PCGamesN.com