▲ Harbour Hide, UK, £3.85m
Where: Near Christchurch, Dorset, 100 miles (161km) from London.
What: A four-bedroom house with private mooring on sailing estuary.
Why: The indoor swimming pool is only 9.5 metres long, but it’s got a jet you can swim against and, for those who have always admired the under-office shark tanks of Bond villains, the pool can be hidden under the floor at the touch of a button. Televisions also hide behind electronically unrolled paintings. All of this wizardry, plus the more mundane features of heating, lighting and music can be controlled by wall-mounted Android tablets in each room.
Who: Knight Frank, www.knightfrank.co.uk, tel: +44 (0)1962 850333
Carlile Place, UK, £5.75m ►
Where: Kings Road, Richmond, London TW10.
What: A six-bedroom detached house in a genteel suburb.
Why: This space-age double cube’s ventilation system replaces the air every two hours, exchanging heat from old air to new. Other devices like solar panels and rainwater harvesting would please local MP and eco-enthusiast Zac Goldsmith. The lighting and audio-visual equipment are all controlled from a central hub. Richmond has the rural delights of quaint shops, a deer park and Thames-side meadows, yet is less than 20 minutes from central London.
Who: Hamptons, www.hamptons.co.uk, tel: +44 (0)20 8940 2772
Quinta Belamandil, Portugal, €4.5m ►
Where: Algarve, Portugal.
What: A 6.6 hectare (16.3 acre) seaside estate with helipad.
Why: This giant holiday home is filled with smart technology. Water is heated by solar power, but electricity or gas can take over. An automatic sound system runs throughout the house and gardens. The latest Toshiba kit takes care of heating and air conditioning.
Who: Portugal Sotheby’s International Realty, www.sothebysrealtypt.com, tel: +351 911 870 217
Vandoeuvres, Switzerland, SFr20m (approx £14.5m) ►
Where: Vandoeuvres, 10 minutes from central Geneva.
What: A five-bedroom, five-bathroom house with nuclear bunker.
Why: This spacious modern house will suit a Geneva-based family who likes to entertain but is worried about an impending nuclear war or environmental disaster. Complementing the fully stocked bunker is a 2,000 bottle temperature-controlled wine cellar, spa, hammam and an integrated vacuum cleaning system. All lighting and heating can be controlled from a central computer.
Who: Chesterton Humberts, www.chestertonhumberts.com, tel: +44 (0)20 3040 8210
1103 South Ocean Boulevard, US, $19.95m ►
Where: Delray Beach, between Boca Raton and Palm Beach, South Florida.
What: A five-bedroom estate with 120ft (37m) of beachfront.
Why: Sports fans might be tempted by the two outdoor 103in underground, pop-up, all-weather flat-screen televisions and 12 speakers that bracket the heated outdoor pool and its amphitheatre.
Who: Premier Estate Properties www.premierestateproperties.com, tel: US +1 561 665 8170 or UK +44 (0)20 7467 5330