A tabletop device uses 1.4 J to drive the symmetric collapse of a 1.8 mm radius vapor bubble in water at 22 bar. Single shot streak imaging reveals a stagnation plasma of 28 micron radius at over 12,000 K and an unprecedented pressure of 3.2 Mbar. Compared to sonoluminescence, the most commonly studied cavitation mechanism, this event is greater by factors of 30-40 in size, 1,000,000 in energy, and 100 in stagnation pressure. This regime of high energy density has previously been accessible only in massive facilities with very low repetition rates.