"I have no mouth yet I must scream" is by Harlan Ellison. And yes, the all-encompassing godlike computer is called AM -- as in "I Am". Whatever abbreviation "AM" started out, it became irrelevant when the computer decided it was God. Or close enough, anyway.

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Fiction has to be plausible. Reality is under no such constraint.

Not "yet", "and".

The aliens in Robert Silverberg's short story, "Passengers"; they temporarily--and totally at random--take over a person's body, forcing them into a fugue state in which they can do all sorts of atrocities that the victim doesn't even remember.

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"Call me old-fashioned, but I think fire is magic. And it scares me a lot."

--The State

Haunted houses on a mega scale...

I don't know about "scariest", but the Knnn from Cherryh's Chanur saga are pretty darn creepy.

How about the not-ill-intentioned but super-fast-reproducing and compulsive "repairing" watchmakers of Mote in God's Eye fame?

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Todd (Bowie, MD, US, North America, Earth, Sol System, Vega region, Local Bubble, Orion arm, Milky Way Galaxy, Local Group, Virgo A Cluster, Virgo supercluster, the universe in which spock is clean shaven)

Quidquid latine dictum sit, altum sonatur.

personal page: http://blog.astrosketches.info

I have been wracking my brain (ow) but cannot think of the title or author of a certain short story. (Maybe someone here will recognize it?) The scariest alien comes from that story, and of course it's a human.

A man is sent to another planet on a diplomatic mission to negotiate an agreement with the planet's ruling committee. He is told that to speak with the commitee he must submit to various trials. These include ritual amputations of - first - fingers and toes, leading to his giving up his arms, legs, and genitals. Finally, he is blinded.

Then he is considered worthy enough not only to speak with the committee but to join it.

Shortly after, a servant informs him that his wife has arrived and wants to speak with him. He tells the servant to cut off one of her fingers.

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Never attribute to malice what can be adequately explained by ignorance or stupidity.
Isaac Asimov

I found the moties in general to be very scary. Just the fact that they were individually so dern likable, & collectively the biggest threat our species had ever encountered. Hmmmmm. Kinda like us?

More like Texans.

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The Devil offered me power. I told him I preferred aperture.

...and one Wyomingian.

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To me, the scariest movie or book alien is the cute yet devastating tribble. You'd be starved as they reproduce on your food supply, and they'll purr at you while doing it. It is so plausible. Take a creature out of it's natural environment and all heck breaks forth.



In real life Australia had a 'cute & fuzzy' rabbit explosion that nearly destroyed the country, as the animals had no enemies, literally eating other critters out of house 'n home.

Not exactly an alien, but in "blood music", we have sentient bacterial colonies that can decide to make individuals sick whenever they want.

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Todd (Bowie, MD, US, North America, Earth, Sol System, Vega region, Local Bubble, Orion arm, Milky Way Galaxy, Local Group, Virgo A Cluster, Virgo supercluster, the universe in which spock is clean shaven)

Quidquid latine dictum sit, altum sonatur.

personal page: http://blog.astrosketches.info

The Amplitur in Alan Dean Foster's The Damned trilogy.
http://en.wikipedia.org/wiki/The_Damned_Trilogy
Telepathic mind controlling squid/lobsters with genetic engineering abilities. He of course also wrote Alien. The man must have some freaky nightmares.

The nerve runners in Frank Herbert's/Brian Ransom's book The Jesus Incident were pretty scary. They would burrow through the victim's skin, then chew their way up the victim's nerves until they died. I always thought that was a pretty frightening concept.

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Yes, they laughed at Einstein, but only because of his silly hairstyle; no one was actually laughing at his science.

The aliens in Dean Koontz's The Taking are rather scary, but then that book has some very sociopathic human characters as well.

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"I took month-long vacations in the stratosphere, and you know it's really hard to hold your breath . . ."

I believe that this is "On the Uses of Torture," by Piers Anthony.

Thanks for reminding me of it. Ugh...

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www.pageatatime.com - Art, Evolution, Painfully Slow Development.

That's a novelization of the movie, he didn't invent the alien.

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"God bless thee, my son; I will give thee the greatest jewel I have ...
"The end of our foundation is the knowledge of causes, and secret motions of things; and the enlarging of the bounds of human empire, to the effecting of all things possible."Trying to make sense of computers, The Error Log.

I stand corrected. I just remembered seeing the novel, haven't read it. One of those odd occurrences when the book is made from the movie.

Far from odd, it’s actually very common for books to be based on films. In the case of Star Wars and Star Trek, it’s hard to keep track of the number of book series that spin off from other book series (not that I particularly want to).

You’d think the straight adaptation of film to novelisation would be dying out now, given that you can own the DVD within a few weeks of the cinema release, but it doesn’t seem to be happening.

Micheal Shea ran a rather similar plotline in The Autopsy, but I think he managed to do a nastier tone. An upleasant little tale, that.

Scary critters of the Lovecraftian persuasion include Ramsey Campbell's The Voice of the Beach (debatable if there's a "true alien" in the story), Frank Belknap Long's The Space Eaters (the story is stilted but the creature is nasty) and various creations of Robert Charles Wilson's from The Perseids and Other Stories.

For a cynophobiac, it's hard to beat the Musk Dogs from Alastair Reynolds' Pushing Ice tho.

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The dog, the dog, he's at it again!