Listing a property with out-of-the-ordinary features is a double-edged sword, real estate agents say. Unusual amenities may draw attention to a listing, but they can also narrow the field of potential buyers.

A house built in the shape of a guitar may be a conversation piece, but, really, who wants to sleep in the frets?

More often than not, unusual features come about because someone created a home to suit his or her own desires, without necessarily giving thought to selling down the road - like the two-story river-rock bathroom in the Topanga, Calif., home of Rita George that she designed and had built by hand. It's part of her all-rock-and-boulder house, constructed by local stone artisans.

To enter the tub and shower, George climbs three rock steps. A cupola ceiling and arched etched-glass windows - made by another local craftsman - complete the stone-castle look.

"This house is part of me," said George, who said she has no intention of selling. "They'll have to drag me out of here when I'm 105. I love this house."

But a Malibu compound was recently listed for sale with multiple one-of-a-kind features. Its owner is Douglas Busch, a photographer who specializes in large-format black-and-whites and whose works has been exhibited in museums. Busch designed and built the complex three years ago.

The 10-acre property, which has a 4,500-square-foot main house, provides plenty that's out of the ordinary. To start, the portion of the roof over the bed in the master bedroom fully retracts by remote control, opening the room to the elements.

Several inches of water cover another flat roof of the multilevel house, and a pump keeps things moving in a babbling-brook kind of way. Steppingstones lead to lounge chairs.

There's a separate sitting-sleeping deck surrounded by water with an outdoor fireplace. "To take the chill off," Busch said.

And that's just the roof.

Busch's detached studio - all 4,000 square feet of it - is completely surrounded by water. Water flows under it from the pond that it sits in, and the front door is reached by stepping-stones. The glass garage-style door that fronts it opens completely, exposing the studio to the elements.

"I keep it open most of the time," he said.

Some of the home's more unusual features reflect Busch's passions.

Take, for example, his feelings about running water. He likes it in the gentle Zen-waterfall way, soothing and quiet - hence the rooftop water elements and the studio-in-the-pond. But he finds water disturbing in the bathtub-roaring-and-splashes way.

So his master tub fills and drains quietly from the bottom. Water runs in - and out - via jets and openings along the bottom perimeter.

His lack of affection for drains carries over into the other bathrooms. The shower in the studio's bathroom is the whole room. The drains are hidden beneath the planks of sauna wood that are the flooring.

There is also a 110,000-gallon swimming pool. Busch claims it is the third-largest private pool in Los Angeles. The spectacular ocean-view property listed for $9.75 million.

The market for properties such as this is small, real estate agent Shirley Sherman said. The buyer of such a home likely would be someone who appreciates its "five-star workmanship," she said - and who probably doesn't have small children.

The granddaddy of houses with outrageous amenities may have been the five-bedroom place that NBA legend Wilt Chamberlain (who long called Philadelphia home) had built in 1971 and lived in until his death in 1999.

Chamberlain installed a gold-lined hot tub, a retractable mirrored ceiling above the master bed, and a wraparound swimming pool that extended into the living room. Subsequent owners removed many of the original features, and the house was recently listed for sale again, at $9.995 million.

Two Hollywood TV writers purchased the 8,000-square-foot house from Chamberlain's estate in 2002 for nearly $3 million, and extensively remodeled it - although the retractable ceiling in the bedroom remained.

The house attracted much attention over the years but wasn't an easy sell. When Chamberlain's estate was trying to unload it, it was initially listed at $7.45 million and later reduced to $4.38 million.

How far is over-the-top when it comes to the rich and famous?

Although publishing giant William Randolph Hearst may have set the bar high with his castle, San Simeon, surely Microsoft Corp.'s Bill Gates has cleared it easily.

Gates' Seattle lakefront home has a 92-foot-long grand staircase. And if you find the 84 steps from the entrance to the ground floor daunting, there's always the elevator.

His 1,000-square-foot dining room seats 24, and the 2,500-square-foot exercise facility includes a trampoline room with a 20-foot ceiling.

The 3,900-square-foot pool building has a 17-by-60-foot swimming pool with an underwater music system and a fossil motif painted on the bottom. Swimmers dive under a glass wall and emerge outdoors by a terrace.