The store has a woozy, laid-back atmosphere. Chopped and screwed versions of songs by Notorious B.I.G., Too $hort and others ooze from the surround-sound system. The display cases teem with what looks like an eternity of Screw CDs and mixtapes.

Rap posters, S.U.C. shirts and beanies and a ton of other hip-hop paraphernalia adorn the walls. In the back is a recording studio where local artists go to cut new songs and tap into the innovative spirit of the man who once walked the store.

Underneath the haze of Houston's hip-hop scene, there was always the beating heart of Robert Earl Davis Jr., popularly known as DJ Screw. It's as if Screw woke up one morning, stuck his finger into the hot, humid Houston air and sensed the city's desire to cool things down. So he went about exploring ways to slow rap music to a crawl.

In the early '90s, this unique sound found its way onto the streets of Houston. It was so original it took on the name of its creator. Screw relied on a slow, laconic sound, a departure from the 808 blasts and drum-driven style dominating the West and East coasts at the time.

If Screw's style had a ­progenitor, it was the blues. It wasn't the type of ­music you expected to hear at a club.

But Screw wasn't just about slowing down rap songs. That's part of it, but it was also an original art form that relied on an innovative technique. It's grown into a lifestyle, a culture and a hip-hop movement in its purest form.

DJ Screw's co-conspirators were equally sluggish in their approach to rapping. For the most part, their lyrics didn't protest anything or threaten anyone, just celebrated their slow-motion lifestyle.

Whereas East Coast MCs were perpetually menacing and hasty, Southern rappers were calculated and relaxed, albeit with the occasional hint of ominous tales. Regardless of the topic, there was always a sense of calm.

Thus the sound of Screwston was born. Not since New York nicknamed itself the "birthplace of hip-hop" in the boom-bap days has one city been so synonymous with a specific sound. Screw's dominance continued to grow even years after his death, as his mixtapes and albums traveled across the Mason-Dixon line.

Then, in the mid-2000s, the tide of history turned in favor of Houston hip-hop's short-lived hegemony as spearheaded by Mike Jones, Paul Wall, Chamillionaire and Slim Thug. Veterans like Scarface, Lil' Flip and Bun B christened their arrival, but one shout-out kept popping up on everyone's records: "R.I.P. Screw."

Today, that familiar name has single-handedly turned Screwed Up Records & Tapes into a monument of sorts. In terms of regional significance, it's to Houston hip-hop heads what Bob Marley's Tuff Gong Studio is to reggae fans and Fela Kuti's Kalakuta Shrine is to Afrobeat followers.

On a global level, its prominence isn't necessarily on that level. You won't find Jay-Z dropping by to record an album there, for example. But you'll see throngs of hip-hop heads popping in for a piece of history.

Lil D, the radiant manager who helps oversee Screwed Up Records & Tapes' operations, estimates that the shop moves about 40 CDs on a good day, and around 80 on a very good day. But he's quick to add that sales have declined significantly as tape seekers migrate online. The store is readying a new Web site to palliate the damages done by those pesky pirates, and also help catalog some of the mixes available at the store.

DJ Screw was such a prolific producer that indexing his tapes is a grueling task. Like the man behind the legacy, the staff is in no rush to move, transferring about three or four new tapes to CD every month.

While nearly 300 mixtapes are accounted for as of this writing, Lil D says another 150 or more have yet to be transferred — not including albums and one-off projects. Oh, and no one knows the exact location of all Screw's tapes.

So, how exactly has the store managed to stay afloat in the age of eBay and torrent sites? Lil D credits the loyalty of Screw fans: "People support us because they know that this is what feeds his family," he says.

Still, not too many businesses can survive on the strength of charity support. There's something else going on here.

"Screw's originality is the key," says Lil D. "There's a lot of people that come out and copy. But you can't duplicate this. A lot of people know it's the real deal, and they can tell the difference between Screw's mix and other people's mix."

Originality aside, Screwed Up Records & Tapes also finds strength in the support of Screw's disciples. If you call the store's answering machine, you're likely to hear the profound basso of Z-Ro calling out the store's business hours.

"You done reached Screwed Up Records & Tapes," recites the Houston rapper. "Our business hours are Monday to Friday..."

Priceless.

Z-Ro, Lil' Flip, Trae and the countless extended members of the S.U.C. family remain staunch supporters of the landmark shop, not because it's considered an honor to be affiliated with the S.U.C. They remain supportive because family was Screw's mantra.