THE scientist in the 1959 horror film "The Killer Shrews" is not only mad but also cheap. Monstrously cheap. To solve the problem of world hunger, he tries to breed humans down to half their normal size. Rather than increase the food supply, he reasons, he will decrease demand. But his penny-pinching plans go awry, naturally, or unnaturally, creating a pack of giant, munchies-afflicted shrews.

"The shrews were actually hound dogs with fangs stuck to their heads and hairy rugs on their backs," recalled James Best, who portrayed the hero, Thorne Sherman. Mr. Best's love interest was played by Ingrid Goude, a former Miss Universe who was, he said "very well-endowed but not very well-paid; she got about 15 cents." Mr. Best, now 78, reckoned that that was about 35 cents less than the budget of the entire movie.

"The Killer Shrews," the masterwork of Ray Kellogg, is one of hundreds of cheap old films now available as ridiculously cheap new DVD's. Because of lapsed or improperly registered copyrights, even some very watchable movies -- among them, Howard Hawks's "His Girl Friday," Marlon Brando's "One-Eyed Jacks" and Francis Ford Coppola's "Dementia 13" -- are now in the public domain and can be sold by anyone.

While overall DVD sales are robust -- last year retailers sold $15.5 billion in discs -- the low-end market is positively booming. Recently, 19 of the 50 top sellers on the Nielsen VideoScan national sales charts were budget DVD's. "The prices are irresistible," said Gary Delfiner, whose Global Multimedia Corporation offers 60 film, cartoon and television titles with prices ranging from 99 cents to $1.99.