Lasers

[ToddG]

Blue is more visible over distance than red. Neither is anywhere close to green, admittedly, but a lot of people seem to think green will get skipped over because blue will be so much cheaper than green, and so much more visible than red, that it will make the best happy medium.

[Ryo]

Your right that blue is easier to spot than red. Looks cool too, but it's a bit fuzzy looking due to my eyes processing the borders of the color. Haven't heard of people not being able to view the green.. interesting.

Here's spectrum I saw on another site.