Typing "robot" into Google yields some interesting results. The number of hits is as staggering as the intensity of interest in the underlying question: Can robots replace humans? We’re not there yet. Although...

A robot with methane-powered muscles
Can robots run without electricity? The University of Texas at Dallas Nanotech Institute has published an article on a methane-powered artificial muscle in the prestigious magazine Scientific American.

Besides being a hundred times more powerful than human muscle, this artificial muscle requires no electrical energy source. Methanol circulates throughout the robot like blood does in people. As in the human body, the muscle converts fuel into mechanical energy and stores what it doesn’t use.

Researchers have also developed a hydrogen-fueled muscle that operates on the same principle. Electrochemical circuits function like nerves in the human body, converting chemical energy into electrical and mechanical energy.

For now, the invention will be used in military applications such as prostheses, or to create wings for insects that would go spy in enemy territory.

Spring cleaning in a snap: Let Roomba do it

You dreamed it; iRobot made it! Anyone stuck with housework will love the independent vacuum cleaner Roomba. The first version of the robot became the best-selling vacuum cleaner in the world. It’s easy to see why people love it: Roomba vacuums all by itself, cleaning even the hardest-to-reach places.

Simply charge it up, press the "power" button, and it starts to spin around, sucking up dust. Roomba can be contained to a designated room with virtual wall units even if the doors are open. The robot even knows how to work its way around obstacles.

The user can choose among three modes to have Roomba clean a specific area, or thoroughly vacuum an entire room. When it’s done, Roomba goes back to its home base to recharge its batteries. Want one? At $279, the price might deter some fans.

Those who do have one have become attached. According to one U.S. study, 60% of Roomba users have given their vacuum cleaner a nickname. And Roomba now has a little brother, Scooba, who “mops” floors all by itself.

Pleo: not just a toy, but a robot with emotions

Kids love robots because they are more than just toys. The company Ugobe has released Pleo, a robot-dinosaur that is sure to find its way into the hearts of children and adults, just like Furby did. This small, 30-cm (12-in) long dinosaur expresses emotions.

With 14 motors and 38 sensors enabling it to perceive and react to stimuli, Pleo has “real personality." It moves, learns, and expresses emotions like boredom and joy. Ugobe is targeting both children and adults with its innovative intelligent robot.

Ri-Man: a robotic assistant for elderly persons with limited mobility

Backed by support from the Japanese government, a research center in Japan called Bio-Mimetic Control (BMC) has unveiled a robot that can help people with limited mobility. The robot can currently carry a 15 kg (33 lb) dummy. The goal is for it to be able to carry a 70 kg (154 lb) robot within five years.

Ri-Man (Robot Interacting with Human) is designed to feel, smell, hear, and see people in its environment. The initiative is welcomed by the public in Japan, where the old outnumber the young. Of course, the price tag for Ri-Man is still unknown.