Strength comparison tests of super massive neodymium magnets.

[BrianHG]

  Strength comparison tests of super massive neodymium magnets.  Enjoy! 

[schmitt trigger]

Not as strong as the magnets in the video, but the magnet used in a hybrid vehicle motor is also ultra strong.

There are Youtube videos, intended for automotive mechanics, which show the assembly and disassembly of those motors.
The videos specifically warn against attempting to remove the rotor from the assembly unless you have the specially designed, very sturdy assembly jig.

The force of the rotor being attracted into the stator can easily crush your fingers.

[Augustus]

...meanwhile at the parcel service 

[raptor1956]

Remember when your mom would tack a floppy disk to the refrigerator with a magnet?

There was a Perry Mason episode where a blackmailer had an audio recording the implicated Mason's client and Mason setup a meeting for a payoff.  Before going to the meeting he acquired a powerful magnet and when the blackmailer should Mason the audio tape Mason pulled it close to the magnet.  He then asked to hear the tape and when played -- nothing.

Neodymium magnets are nasty and you best not get your fingers or penis caught between it and some steel.


Brian

[digsys]

  ... Not as strong as the magnets in the video, but the magnet used in a hybrid vehicle motor is also ultra strong ....
The videos specifically warn against attempting to remove the rotor from the assembly unless you have the specially designed, very sturdy assembly jig.
The force of the rotor being attracted into the stator can easily crush your fingers. 

I have a few solar car wheel motors and magnet rings in the garage, plus the dis/assembly jig. And yep, they are seriously dangerous to handle.
The rule is, IF you ever have one slip while splitting the wheel, don't bother trying to recover it. Even the tiny ~3cm x 1cm individual pieces are near
impossible to pull apart. Awesome stuff. Somehow, I have to set up jigs to do heat / longevity profiles on them. That's going to be interesting :-)
.. so fingers is the LEAST of your problems !! :-)

[max_torque]

I worked for a company developing high performance electric motors for EVs and we had a great "trick the new starter" routine.  We'd position two PM rotors on a steel topped work bench, they LOOK identical, but one has been de-mag'd (magnets heated to beyond their Curie Temp).  An engineer tells the New Guy and an existing tech to go "grab those rotors" and existing tech leads, easily picks up rotor which isn't magnetic, then the fun starts whilst the New Guy tries to pick up the (extremely) magnetic one......     

[Messtechniker]

HDDs have strong slightly brittle magnets within.
I extract them, and glue them under a yoghurt pot or similar.
Handy for collecting small screws, nuts, washers etc.
when disassembling something.