This Stoned variant will activate on the birthday of Michelangelo Bounnaroti, who was born on March 6. 1475. It will then overwrite most of the hard disk. Structurally it is similar to the 'Stoned' virus, but it will infect non-360K diskettes correctly.
It is not an easy task task to recover from the activation of Michelangelo. The virus overwrites the first 17 sectors on heads 0-3 on the first 256 tracks of the disk the machine has been booted from.
There are several known variants of this virus - some of them do not activate at all. There are also at least two file viruses that occasionally 'drop' the Michelangelo virus to hard drives master boot sector, namely Prague.Pizza and HLLC.Enrico.A.
Michelangelo used to be very widespread in the early 1990s. Nowadays it is almost extinct.