No, they don't. I hate cigarette smoke but the E-Cigs don't smell bad at all. I haven't smoked for years and I took a couple puffs on one and realised that they have something there. I don't mind them at all.
Nope. But they won't do you any good either. If you really want to quit, forget about that crutch and look into hypnosis. I work with numerous clients for smoking cessation and have some great success. It works. Look into it.
E cigarettes do not harm others while you smoke. This is because they are not products of combustion. They also don't produce toxic smoke as other cigarettes. They normally vaporize a liquid solution into an aerosol mist when inhaled.