absolubtely not, ethanol is still fuel, and its actually better for you car and the enviroment

Sorry, but the original poster is not asking about a car engine. A small motor, especially a carbureted 2 stroke that uses oil mixed in the gas, such as a chain saw, will indeed be damaged over time. The alcohol content will disperse the mixed oil as it is atomized and the spray "hits" the piston. The oil is then essentially washed away before it can provide the proper lubrication. This is where the engine wear will occur the most, on the intake side of the piston, and when it has gotten bad enough, the engine will cease to run due to the loss of compression. Usually you can get away with replacing just the piston and ring, but sometimes the cylinder is also damaged as well. It's not an immediate problem, but a day in, day out, four hours a day use of a chain saw will probably last 6 months or so. Many small engine manufacturers will even consider your warranty void for damage such as this. As it means you did not use the proper alcohol free fuel when operating the engine, it's usually well defined in owner's manuals to use ethanol free fuel. It's also pretty non disputible as well, since when the piston is only worn/damaged on the intake side, it means that either you didn't have an air filter on, or were using poor fuel. Overall, in a low use homeowner engine, i wouldn't worry too much about using an ethanol mix. By the time this damage will compound, the rest of the machine might be worn out beyond reasonable repair anyway. If you are a professional user, and demand a high level of long term quality use out of your equipment, i'd do my best to find non-oxygenated gasoline. You could also use aviation gas, it should also be alcohol (ethanol) free, and will be high octane, which is also good for many small motors.