I have a hard time with this topic. Of course the only thing that ever gets covered in main-stream tech media is the abuse by patent trolls suing Company X because they are using their "electronic key-input device" patent to type on their computers. We all roll our eyes and go "Damn these patents! DAMN THEM!" But then I think of the purpose of the patent system in general: to protect and encourage innovation. I think…
Not really.
Oh, you can't patent a perpetual motion machine, but you can patent an improvement to a process without showing that you can implement the whole process.
Suppose that I come up with an improvement in making steel in massive amounts. Do you really think that I shouldn't be allowed to patent it without building a large steel mill? (Two interesting cases are the lone "nut" and a university researcher.)