Subject: Electricity generators

I remember from my physics classes at school that one can generate an 
electrical current in a wire using magnets, and moving the wire 
through the magnetic field.  Would it be possible to set up some 
magnets in a way that they could oscillate in relation to each other 
without any external aid?  Could this device then be used to create a 
constant electrical current?  I know that air friction and gravity 
would eventually cause the magnets to stop oscillating, but what if 
this device were to be suspended in space?  And how long do magnets 
last anyway?  

Re: Electricity generators