Sure, a handheld personal digital assistant can beep its brains out to remind you of a noon appointment, but what if you left it at home? The beeping would be for nothing -- unless that Palm Pilot could follow you, chase you down, even bump into you to get your attention. It's not science fiction, and in fact, researchers at Carnegie Mellon University's Robotics Institute think everyone should have such a personal robot. So they've created a do-it-yourself kit and published the simple recipe on the Net -- $250, 11 parts and 15 steps later, you've got a Palm Pilot Robot. "Well, there is one step where you have to do some soldering," conceded Palm Pilot Robot Kit project founder Illah Nourbakhsh. "Other than that, this is really something anyone could do." It might be the perfect use for that already outdated personal digital assistant you have lying around on the dresser. Robot kit creators wanted to make construction as easy as possible to encourage imitation, so the Pilot project Web site offers explicit instructions written in cookbook-recipe style, complete with large photographs for each step. The end product would never be mistaken for R2D2, or even for Sony's Aibo -- it looks more like a Palm Pilot with wheels glued onto the bottom and some exposed wiring. But it does work, and because software developers can write new programs for the Palm, it's fully programmable. Its most impressive function to date is the ability to wander around a room, map its objects and remember its shape. The device can then be instructed to return to a specific area in the room. "We hope to build up a community of users who will then write lots of applications for it," said Nourbakhsh, a robotics professor at Carnegie Mellon. Among the possible applications: the device could follow you around, useful for anyone who's ever lost a PDA. Ambling Palms could also wander around a conference room on their own, gathering virtual business cards as they go, avoiding the need for personal introductions. When the idea caught the attention of high-tech discussion Web site Slashdot.org, one poster there immediately thought of the device's prank potential. "Quick! Someone slap a Palm VII with a Palm camera on this thing!" the poster wrote. Palm VII's can receive and send commands wirelessly. "Wal-mart Employee: 'Security to hardware. We have a code 4427. I repeat, we have a small robot loose in the store.' All while geeks watch the live webcast from the bot." There are three critical components to add to the portable device that make it really auto-mobile: infrared sensors, which act as the robot's eyes; "smart" motors, called "servos", which are capable of taking electronic commands; and, of course, wheels. It's all tied together through a circuit board that translates computer-like commands from the Palm Pilot into a single language called "pulse width modulation" that the motors speak. Most important, the robot is built entirely from off-the-shelf parts that are cheap and easily accessible, said Matt Mason, another Carnegie Mellon robotics professor. The servos, for example, cost only about $12, thanks to a burgeoning hobby market. The motors are most commonly used in model airplane construction. "Being able to build them quickly and cheaply makes them accessible to so many people," Mason said. Nourbakhsh is unabashed about the agenda his project has -- forget the do-it-all megarobots that clean the house, make coffee, provide companionship -- and won't be seen for decades. He wants the robot revolution to start immediately, with small, simple, cheap robots populating people's homes as quickly as possible. "The idea for the Palm Pilot Robot is born out of the concept of taking robots and making them more a part of environment we live in," said Nourbakhsh. That way, creative and useful applications will develop much more quickly. "It's fun to think about creating a robot from a device with a lightweight, small processor. It's already portable and has its own power and screen. So we thought, 'What if it could move?'" There are other robots making their way into peoples' homes these days: Lego's Mindstorm, a set of robot building blocks designed as an educational toy for children over ten. But Mindstorm robot's are "temporary", said Nourbakhsh, and they lack the programmability offered by a Palm Pilot. According to the researchers, Palm is pleased with the research at the Robotics Institute and has promised to contribute some of its devices to the effort -- no word yet on the company's opinion of its aesthetics. But Nourbakhsh said the bot could also be built with other PDAs, such as a Windows CE device, or even with a scientific calculator. The student who actually built the Pilot kit is 17-year-old freshman Grigoriy Reshko, a native of St Petersburg, Russia. His family moved to Pittsburgh five years ago. He says since the Pilot robot kit page appeared on Slashdot last week, he's been deluged with email. Already, five readers have begun construction. "They promised to all send pictures, so we'll see if it works out," he said. To have your say online click on the TalkBack button and go to the ZDNet News forum. Let the editors know what you think in the Mailroom. And read what others have said.