Here are some pictures of an interesting lock I own. It's made by FEDERAL, it has a magnet in the key and is a pin-in-pin Lock.
It was quite difficult to dismantle, especialy because I wanted to not file the key (I have only one), but I wanted to keep the order of the driver pins of the lock, but with some ingenuity, it was made possible and now, I will never file any key for taking a lock apart ! (and it is a european cylinder, so no rear-shim possible).
Lets start with the pics
Here is the lock itself :

And now, the inside :

You can notice the little ball on the right. It has no use but keeping the plug at position you can withdraw the key easily (when you use the key, it feels like when you have a sidebar in the lock, you feel like a "click" when you are at the position you can withdraw the key). No need to wonder for picking. (it could probably annoy a flip-it tool)
And now, the functioning of the magnet :
with no key :

with the proper key (or any magnet at the right place, actually) :

I've been told that the place of the magnet can change from one cylinder to another, but you can find the place very easily, because there is no pin at that place

Another interesting thing with this lock is that there are 4 pin stacks, while there are 5 locations on the key. It feels more secure, probably...
Hope you enjoyed the pics and explanations

FrenchKey