I used to work next to the french Laboratoire National des Champs Magnétiques Intenses (Powerful Magnetic Field National Laboratory) and was lucky enough to visit it once during the yearly Science Day (why don't we have this in the US?).
They claimed they had the second most powerful magnets in the world, IIRC behind the Fermilab, at about 32T (again, IIRC). Note that this is a sustained magnetic field, not transient as the OP's record. (still, hitting 100T without destroying the magnet is one hell of a feat! Now if only we could find a source of power to sustain such a field...).
32T is extremely high, more powerful than any natural magnetic field on Earth (according to WP, the Earth's field is about 25uT at the equator to 65uT at the poles). The most powerful permanent magnets (rare-earth) can achieve a little under 1T, and good luck getting that magnet off a piece of steel. 32T is achieved only in a space about the size of 2 coke-cans at the center of a large cylindrical apparatus that is the concentric electromagnets. But even at such a strength, the fields we make are dwarfed by stellar and interstellar magnetic fields, that have been calculated to reach hundreds or thousands of Teslas.
Fun facts: they run the magnets at night, when power is significantly cheaper. They have big banks of capacitors and batteries for spare surge power. The (classical) electromagnets aren't built by spooling wire on a tube, because wire isn't thick enough the sustain the kind of current that goes through. Instead they take a thick copper tube that they slice in a spiral and insert an isolator in the spacing.
Their most powerful magnets were formed of a core superconducting electromagnet surrounded by standard electromagnets. The cost of superconducting materials is what prevent them from making more powerful stuff.
But despite all that, I'm still not sure what kind of experiments require such powerful magnetic fields. Such awesome engineering, so few applications...
