Most recent answer: 10/22/2007
Can certain magnets be altered to only attract certain metals and/or other magnets, as opposed to any metal or magnet that happens to be within that magnets range?
Its pretty clear from your question that you are asking about special types of magnetic fields, not special geometrical shapes or some other such trick. The answer then is no. There are only a very limited number of known long-range fields, i.e. fields that extend over perceptible distances. These are electromagnetism and gravity. The magnetic part of the electromagnetic force is a simple thing, which does not come in all sorts of flavors. The magnetic field doesnt bear any traces of what material it came from.
(published on 10/22/2007)