"But just because you can't get them doesn't give you the right to steal them."

FOR some gamers, thrills do not require state-of-the-art 3-D virtual environments and the latest Xbox or PlayStation. Clunky old-fashioned graphics, ultra-simple controls and crude, spooky sound effects may have an odd sort of appeal.

That's why Spy Hunter, Donkey Kong and Pac-Man are hotter than ever. Now that Culture Club and Wham! have regained their cachet and disco is cool, the tech world is also being invaded by retro-chic.

But how to return to these games without dragging out a dusty old Atari? Increasingly popular software programs called emulators now translate code from older games into language that a latter-day computer can read. Most game emulators are available for free downloading on the Internet, as are hundreds, even thousands, of games.

Emulators are easier to download and use nowadays, adding to their popularity. "Most emulators have been around for many years now, and the interfaces have matured,'' said Bradford W. Mott, project manager at Stella, a popular Atari emulator. "This makes it easy for the average computer user to have access to them."

But game companies and software trade associations are not pleased with the wide array of games and emulators available online. Most sites carry disclaimers saying that the games are meant to be downloaded only by users who already own a legal copy.

Some sites, like pdroms (www.pdroms.de), offer games that are in the public domain and legal for downloading. Intellivision Lives (www.intellivisionlives.com) and other sites have acquired the rights to offer some games online. But many sites offer pirated material and are thus illegal. Some emulator sites are also illegal, since they copy original copyrighted code.

Most users don't seem to care either way, as long as they can play their old games.

"I grew up in the 80's, so I remember the good times I had with Pac-Man, Donkey Kong, etc.," said Tony Smolar, who writes about emulator software for his Web site, emulators.Atari.org, and loves getting the chance to relive those times on his PC.

Popular emulator Web sites include NESten (tnse.zophar.net/NESten.htm), Mame (www.mame.net) and Stella (stella.sourceforge.net). Many emulators run on Windows 95 or later, but some are for Macs and a few work with systems like Linux or DOS. Stella focuses on Atari games, NESten on Nintendo and Mame on arcade games.

Both emulator software and game files (known as roms) are generally downloaded as zip files. The arrows and other keyboard buttons act as controllers.

Old games are history lessons, harking back to a time when looks were not everything but simplicity was. Atari's Pac-Man is like a ghoulish experiment gone wrong. Activision's Pitfall looks like a third-grade class project, with sounds about as sophisticated as a watch alarm. Spy Hunter's trees look like lumpy mushrooms, and Space Invaders still uses some of the least sophisticated graphics known to modern man.

Yet, especially for those who played the games as children, they offer plenty of fun.

Darek Mihocka, a founder of Emulators Inc. (www.emulators.com), which offers Xformer 2000 and Gemulator, free emulators that help run the old Atari computer systems on a PC, contends that one reason the games are popular is that they are more intelligently programmed than today's. Creators had to think more because they had no fancy graphics to hide behind, he said.

"Despite running on one-megahertz processors and in 4K of RAM and with ridiculously crude graphics,'' he said,'' the games from 20 years ago such as Star Raiders and Space Invaders and Robotron and Joust and Pac-Man are simply more fun to play, more interesting," he said. "They're simpler, yes, but written for a pre-MTV generation."

Although the International Digital Software Association has expressed concern about the legality of much of the retro-game downloading, members of its anti-piracy team say they put a much higher priority on cracking down on pirated versions of newer games like those for PlayStation 2 and Xbox, which are more widely coveted.

"We have a fixed amount of resources, so we have to make choices about what we're going to look for," said Ric Hirsch, senior vice president for intellectual property enforcement for the association. Of the 30,000 software-piracy cases on which the association took action last year, only a few hundred involved vintage games.

Many emulator makers say their products, unlike most downloaded games, are not illegal. They compare emulators to DVD or CD players, which are still legal even though they can play pirated DVD's or CD's.

At emulators.Atari.org, links to sites providing game downloads warn: "The sites below contain commercial Atari software. They are provided for convenience only. If you download a program that you don't own, it is illegal - even though these programs are no longer available commercially. You've been warned."

But even those who still have the cartridges for the old games will have a hard time using them; some devices will connect old consoles to a PC or a Mac, but for the PC especially they are few and far between. And Jason Allen, anti-piracy investigator for the software association, contends that it is illegal to download pirated software, whether you own the original or not.

"Game players think it's O.K. to share these games," he said. "But just because you can't get them doesn't give you the right to steal them."

Mr. Hirsch of the software association said that although emulators are usually intended to play pirated games, they are not illegal if they do not directly copy any copyrighted code. Figuring out what has been copied and what has not is a very difficult process, he added.

"You'd have to look at the code of the emulator,'' he said. "We really don't have the resources to go through that, so it usually flies under the radar."

To avoid emulators altogether, sites like Download.com and Halfpricebooks.com allow users to buy or download updates of classic games that do not require emulation. There is also the popular Activision Anthology ($30 for PlayStation2). But for old hands like Mr. Smolar, it is not the same.

"It's similar to music," he said. "If you love a certain song, and someone does a cover version of that song, you may hate the cover version, even though the person who covered it may be a technically better singer. And maybe the song does better on the charts than the original. But still, for you, it lacks something the original had."