But that's just the tip of the iceberg for Australia's biggest nerd, whose entire house is connected to a central processor and can be controlled remotely via a computer or mobile phone. Teeming with technology, the abode conjures up images of The Jetsons but, much to the surprise of visitors, the house looks no less ordinary than a typical suburban dwelling. Wires, switches and gizmos are concealed, true to Oxer's philosophy of "having everything work invisibly".

A magnetic switch installed inside his letterbox detects when mail is inserted and occupants are notified via either the house computer, email or SMS. The garden irrigation system, too, is fully automated and computer-controlled. Oxer's doorbell doesn't ring - instead, button presses are detected by the computer, which then activates a camera to stream video to TVs around the house showing who is at the door. If nobody is home, a picture message is sent to Oxer's mobile and he can choose to let the person in remotely. Inside, curtains, doors, lights and windows are all wired up so they can be controlled electronically.

"You can go to bed and realise that you left the light on at the other end of the house and be able to turn it off without getting out of bed, using an interface on a mobile phone or using a telephone keypad," said Oxer. "You can do things like issue a single command when you leave the house to tell it to go into lock mode and know that every single door is locked, all the curtains are closed and all the windows are closed, without checking them individually."

In the bathroom, lights and curtains are computer controlled and a keypad on the wall lets Oxer set the water temperature. Issuing the "shower" command turns all the lights on, closes the windows and curtains and sets the water temperature to 41C. Oxer, who recently retired as head of the Linux Australia community group, holds down a full-time job as technical director of Internet Vision Technologies, which he formed in 2000. He said the entire home automation project cost him "a couple of thousand dollars" because he did most of the work himself.

"The major cost is time rather than money because a lot of what I've done has been modifying off-the-shelf equipment rather than buying expensive equipment designed specifically for [home] automation," he said. Oxer lives in the high-tech house with his wife, Ann, and their two children. Far from eating into precious family time, Oxer's electronics obsession - sparked by a technician who lived in a bungalow at the back of his childhood house when he was five - has actually turned him into a trophy husband.

"She [Ann] actually finds it quite entertaining and whenever I've done something new and guests come over she's the first person to go around demonstrating it," he said. One of Oxer's next projects is to modify the bathroom scales with a Bluetooth-enabled mini computer that reports weight measurements to the house computer. The data would be logged in a spreadsheet, allowing graphs to be generated showing progress over time. Another plan for this year is to modify his car with a Linux-based computer to allow constant access to the internet. It could then talk to the house computer and "report back information from the engine management system and GPS data".

Asked for the practical uses of such a system, Oxer said he wasn't exactly sure yet. Indeed, many of Oxer's projects were started purely for the challenge and the practical benefits only became clear once they were completed. "I treat it like a toy and I have a lot of fun modifying and reinventing things, so it's a hobby really," Oxer said.