I would also point out that some, mostly the type that engrave metals, of lasers do not trigger a blink response because they are in the deeper bands of IR. So all you will notice is your sudden lack of depth perception, or vision at all. I found this horrifying quote from Wikipedia:
"A pop or click noise emanating from the eyeball may be the only indication that retinal damage has occurred i.e. the retina was heated to over 100 °C resulting in localized explosive boiling accompanied by the immediate creation of a permanent blind spot."
And seriously, a $300 pair of safety goggles can cover a wide swath of potential lasers, chump change to the several thousand most of the good machines cost.