Despite the smart-arse remarks, it's interesting that no-one here seems to have made a serious attempt to answer your original question. Makes me wonder if some people actually know.
The magnet idea won't work for one simple reason: Newton's Third Law of Motion. For every action there is an equal and opposite reaction.
Although the magnet would attract the fuselage upwards, the fuselage would also be attracting the magnet downwards. These two effects would cancel themselves out.
Think of it this way: Sit on a chair, grab the sides of the chair with your arms, and then try to use your arms to lift yourself and the chair off the ground. It's exactly the same situation. You're the magnet, the chair is the aeroplane.
The problem is this - when you pull upwards on the chair there is an equal and opposite reaction force downwards. This is Newton's Third Law of Motion. As you pull upwards with your arms, the reaction force simply presses the rest of your body harder against the seat of the chair. These two forces cancel one another out. This cancellation means there's no remaining force to lift you off the ground.
There's a similar question which says: Why not put a big fan on a sailing boat - when there's no wind, you can turn on the fan and use it to blow the sails along?
It doesn't work for the same reason. As the fan blows the air forwards, an equal-opposite reaction force tries to push the fan backwards. These opposing forces cancel one another and, again, there's no result.
The only way to overcome this is to make sure that the reaction force works in your favour. A rocket doesn't lift itself into the sky - the lift is simply the reaction force to the thrust of the engines pushing in the opposite direction.
You CAN lift yourself and the chair off the ground. But you have to make the reaction force work FOR you. You don't do it by using your arms - you do it by using your feet to push against the floor. The reaction force then pushes you upwards.
[Edited 2005-07-16 12:25:21]