"Watchers" (the one with the smart dog, Einstein) was made into four movies ( I, II, III, and Reborn ) released in 1988, 1990, 1994, 1998, respectively, none of which do the book justice or are worth watching.
"Mr. Murder" was a TV mini-series in 1998. I think one of the Baldwins was the main character. Also not worth watching.
"Intensity" was also made into a TV mini-series in 1997. This one was spectacularly done. John C. McGinley's portrayal of Edgler Vess was chilling. Definitely worth watching if you can find it (I can't!).
"Hideaway" was done in 1995, and starred Jeff Goldblum and Alicia Silverstone. Not a bad jump from book to screen, but not the best.
"Phantoms" was released in 1998, starring Ben Affleck and Rose McGowan. Fairly true to the novel, not a bad movie.
"The Servants of Twilight" was released in 1991. Not a bad adaptation, but with a different (not entirely disappointing) ending.
"The Face of Fear" was released in 1990. I haven't seen this one.
"Sole Survivor" was a TV mini-series in 2000. Haven't seen this one either.
"Whispers" was released in 1989, and again, I haven't seen it.
If anyone knows any more (there are a few concepts and novellas listed at IMDb.com) let me know where to find them!
PS: Let's all hope to god that Kutcher isn't Jack!