Yes i have read a lot about it while in school but never got to see one.
Quantum computers are different from the current computing paradigm because they employ fundamentally different physics from the current computing paradigm. One thing that we have discovered about quantum physics is that it is inherently hard to calculate the detailed behaviour of a quantum mechanical systems on a regular computer. This has lead to the almost tautological idea that if we could make a machine, employing quantum physics, which could simulate the behaviour of any quantum mechanical process in general, then our machine would be able to do things that a classical computer could not.
Great picture and post.